Table Of ContentsDerailleur Systems

Front Derailleur AdjustmentsRear Derailler Adjustments

(derailleur)Rear Derailleur OverhaulCutting Cable HousingShift Levers (shifters)Chain LineBar End Shifter ServiceShift Housing Length

Bottom BracketsCartridge Bearing Type Bottom

Bracket Service (BBT)Brake Service

Linear Pull Brake Service (V-brake style)

Housing LengthBrake Levers

Cassette and Freewheel ServiceCassette and Freewheel Removal

Crank ServiceCrank Installation and Removal-

Square Spindle TypeRemoval of Cranks with

Damaged Threads (squaretype only)

Trouble Shooting a Creaky orNoisy Drive Train

Headset ServiceThreadless Headset ServiceStar Fangled Nut Installation

Chain repair and serviceChain Installation- derailleur

bikesChain Length Sizing

Tire and Inner Tube ServiceInner Tube RepairTire and Tube Removal and

InstallatonMiscellaneous

Bike Washing and CleaningCommon Tools

Derailleur Systems

Front DerailleurAdjustmentsUseful Tools andSupplies

Repair Stand, holds bike securefor easy work.

Hex wrenches as needed.

Screwdriver (#2 Phillips orstraight blade)

Light liquid lubricant

Derailleur cable inner wire andhousing as needed

Caliper or metric ruler

Cable end caps and housing endcaps as needed

Rags

This article will discuss the basicadjustment of the front derailleur.See also related articles:

This article assumes the derailleuris compatible with the shiftingsystem and is not extremely wornout. Cable and housing length is notcovered in the article, see How do Icut cable and housing and how longshould housing be?

Service ProceduresThe front derailleur simply shoves

the chain off one front chain ringand onto another ring. The cagesurrounding the chain is pulled inone direction by the inner wire. Aspring in the derailleur returns thecage to the other direction whenthe inner wire is relaxed. A properlyadjusted front derailleur should shiftthe chain between the frontchainrings but will not throw thechain off the rings. The basicadjustments for the front derailleurare the height, rotation, limitscrews and inner wire tension(index setting).

It is generally a good idea tolubricate the pivot point of the front

derailleur with a light lubricant. Thecable inner wires should also belubricated. If you have loosen theinner wire pinch bolt, lubricatethose threads as well. Whentightening this pinch bolt, secure toapproximately 30-40 inch-pounds.This is about 10 pounds of efforthold a wrench 3 inches from thebolt.

Front Derailleur HeightBefore checking limit screwadjustments, check the derailleurpositioning. If the derailleur cage istoo far above the large chainring, itis more likely to shift poorly. If the

derailleur is too low, it may scrapeagainst the chainrings or jam thechain when shifting.

Some front derailleur models do nothave height or rotationadjustments. These models mounton a plate and both height androtation settings are pre-set.Additionally, some bikes have abracket commonly referred to as a"œbraze-on" for front derailleurmounting. This bracket will allowlimited height and rotationalsettings.

1. Inspect height alignment offront derailleur. The outer cageplate must be positioned over

the largest chainring whenviewing height. Simply grab theexposed front derailleur innerwire until outer cage plate isdirectly over outer chainringteeth. Use care to not shift thederailleur cage past this point.Note height and direction ofchange needed. It is thennecessary to relax the cable toloosen the mounting bolt andraise or lower the height asneeded.

2. The gap between the teeth ofthe outer chainring and loweredge of the outer cage plateshould be 1-2mm, about the

thickness of a penny. Using apenny or a dime as a feelergauge, fit it between thechainring teeth and the cageplate. It should just fit betweenthe teeth and plate.

3. To lower cage, release innerwire tension completely by

shifting to innermost chainring.Note angle of outer cage platerelative to chainring.

4. Front derailleur clamps typicallyleave a mark on the frame,which is useful as a referencewhen changing height. Loosenderailleur clamp bolt, changederailleur height, and returncage to same rotation relativeto chainring. Tighten clampbolt. Move outer cage plateover outer chainring, and checkheight again. Repeat thisprocess until cage plate heightis 1-2mm above outerchainring.

Front DerailleurRotational AngleThe front derailleur cage should beapproximately parallel to the chain.If the derailleur cage is rotated toofar from this position, it will shiftpoorly. If the derailleur mount is aclamp type, its rotation can bechanged. Generally, the outer cageof the front derailleur should bealigned to the chain. The middleimage below shows adequatealignment.

1. Shift chain to outermostchainring and outermost rearsprocket.

2. Sight chain from directly abovechainrings. Consider the chain asrepresenting a straight line.

Compare this line to outerderailleur cage plate. Outer cageplate and chain should beparallel. Keeping the cage andchain parallel will minimize therisk of the chain jumping off theoutermost ring. If cage is notparallel, there will be a relativelylarge gap at either the back orthe front end of the cage, andthe chain may over shift.

3. If derailleur cage needs to berotated, note direction of desiredrotation.

4. Release inner wire tension byshifting to the innermostchainring.

5. Many clamps leave a slightmarking on the frame. Use thisscarring as a reference whenchanging height. It is alsopossible to use a pencil to maketwo reference marks on theframe, one for height and asecond, vertical mark, toreference rotation. Use themarks to avoid inadvertentlychanging height.

6. Loosen clamp bolt and slightlyrotate in correct direction. Usecare not to change height.Tighten derailleur clamp bolt.

7. Shift to outer chainring andobserve rotation alignment.

Repeat adjustment if necessary.

NOTE: Some front derailleur modelsdo not have height or rotationadjustments. These models mounton a plate and both height androtation settings are pre-set.Additionally, some bikes have abracket commonly referred to as a"œbraze-on" for front derailleurmounting. This bracket will allowlimited height and rotationalsettings.

Front Derailleur LimitScrew SettingsLimit screws stop the inward andoutward travel of the front

derailleur cage. Limit screws aremarked "L" and "H". The L-screwwill stop the motion of thederailleur toward the smallestchainring. The H-screw will stop themotion of the derailleur toward thelargest chainring.

If the limit screws lack any marking,you will need to determine whichare the "H" and "L" by testing.Begin with the chain on thesmallest cog. Relax the cabletension completely using the cablebarrel adjuster. Place a hand on thederailleur body to feel for anylateral motion, and select onescrew to turn one full turn clockwise

and then counter-clockwise. If youfelt motion in the derailleur, this isthe "L" screw. If there was nomotion, do the same test with theother limit screw. You shouldconsider marking the "L" screwpermanently. The other screw bydefault is the "H" screw.

Although the limit screws will stopthe derailleur, it is the inner wireand derailleur spring that make thederailleur move. If the inner wirehas too much tension, the derailleurwill not rest on the L-screw stop. Ifthe inner wire tension were tochange, the derailleur inner limitwould also change, possibly causing

the chain to fall off the rings.

Front Derailleur -Adjusting L-screwThe L-screw controls the inwardmost travel of the front derailleur.Set adequately, it allows the chainto shift to the smallest ring, but notbeyond so it falls off.

1. Shift chain to innermost rearsprocket and innermost frontchainring. Inspect derailleur formarking indicating "L" screw.

2. Check inner wire tension. Itshould be fairly loose at thistime. If inner wire is taut, turn

barrel adjuster clockwise intohousing. The barrel adjuster istypically located where the cablehousing enters the shift lever. Ifbarrel adjuster is already fullyturned into housing, loosen innerwire pinch bolt, slacken innerwire and retighten bolt.

3. Sight gap between inner chainplate and inner cage plate. Onlya small gap should be visible,about 1/16" or 1mm, about thethickness of a dime.

4. Pedal bike slowly and continue tosight gap. Set clearance attightest point in chainringrotation. Adjust L-screw so thereis a small gap between inner

cage and inner chain plate. Pedalbike and check that chain is notrubbing cage as chainrings turn.

If there is no gap and chain isrubbing cage, loosen L-limitscrew 1/8 turn (counter-clockwise). Inspect for gapagain and repeat until slightgap appears. 2. If the gapappears larger than 1mm atits widest point, tighten the L-screw, in small increments,until the gap closes.

5. Test the shift by shifting chain tonext chainring then shift back tothe innermost ring. Do not usethe shift lever. Pull on the inner

wire to shift the derailleur. Usingthe lever may confuse limitscrew issues with cable tensionissues. If chain shifts quickly,limit screw setting is adequate.

6. If the shifting appears is slow(requires more than one pedalrevolution to initiate shift), turnL-limit counter-clockwise 1/8turn and repeat test. Repeat 1/8-turn increments until shifting isadequate. The gap will openwider than the 1mm target, butwill still be as small as possiblewith adequate shifting.

7. If chain is shifting beyond theinner ring and falls off the

chainring, gap may be too largeor cage alignment may be off.Tighten L-screw 1/8 turn andcheck shift again. If chain endsup rubbing inner cage ofderailleur, yet still drops off innerring when shifting, otherproblems such as chain line orderailleur rotation exist.

Front Derailleur-Adjusting H-screwThe outward travel of the frontderailleur is stopped by the H-screw. When viewing the H-limitadjustment, make sure there isenough tension on the inner wire by

either keeping extra pressure onthe lever, or by pulling the exposedinner wire taut by hand. Use a ragto protect your hand if pulling theinner wire. After the H-screw isadjusted the inner wire should bere-tensioned to assure propershifting.

1. Shift to outermost sprocket inrear and outermost frontchainring. Inspect derailleur formark indicating H-screw.

2. Pull inner wire with hand toincrease tension to insurederailleur is against H-screw.

3. Maintain full pressure on inner

wire and check gap betweenchain and outer cage plate. Onlya small gap should be visible,about 1/16" or 1mm. Pedal bikeslowly and continue to sight gap.Set clearance at tightest point inchainring rotation.

A. If chain is rubbing cage,loosen H-screw 1/8 turn andpull fully on inner wire. Checkgap again.B. If chain is not rubbing,

tighten H-screw repeatedlyuntil chain is 1mm

4. Test shift to the large ring. Shiftderailleur from next to largest tolargest ring using hand pressureon inner wire rather than shiftlever. If shifting is slow, loosenH-limit screw slightly and repeattest. If chain shifts off theoutside of the large chainring,the outer-limit is set too loose.Tighten H-screw limit and testshift again.

Front Derailleur-Adjusting Indexing(Three Chainring Bikes)

Some front derailleur systems havean index setting. If the shift leverhas three distinctive stops or clicks,it is indexing. If the front shift leveris friction, there is no index setting.If the front shift lever has multipleclicks, such as some twist grip styleshifters, it is shifted similar tofriction levers. Set indexing onlyafter completing all adjustmentabove.

1. Shift chain to middle chainring inthe front and innermost rearsprocket.

2. View gap between inner cageplate and chain. Gap should beas small as possible without

rubbing chain.

3. To reduce gap, increase innerwire tension by turning barreladjuster counter-clockwise.Adjusting barrel may be on

frame or on shift lever. Checkgap again.

4. If chain is rubbing cage, turnbarrel adjuster clockwise, orinward toward shifter body.

5. If barrel adjuster is all the way inor out and no adjustment ispossible, reset inner wiretension. Shift to innermostchainring and loosen inner wirepinch bolt. Pull wire gently withfourth-hand tool and tightenpinch bolt. Begin adjustment ofinner wire tension as above.

6. Test shift of front derailleur to allthree front chain rings. If thederailleur rubs in the largestfront chainring, double check H-limit screw and inner wiretension, which may be too loose.If chain is slow to shift tosmallest chainring, double checkL-limit screw and inner wiretension, which may be too tight.

Front Derailleur-

Adjusting Indexing(Two Chainring Bikes)Some front derailleur systems havean index setting. If the shift leverhas two distinctive stops or clicks, itis indexing. If the front shift lever isfriction, there is no index setting.

1. Shift chain to outer chain ring inthe front and outermost rearcog.

2. View gap between outer cageplate and chain.

3. If outer cage plate clears chain,index setting is adequate.

4. If plate is rubbing chain, increase

inner wire tension by turningadjusting barrel counter-clockwise and check again.

5. If barrel adjuster is all the way inor out and no adjustment ispossible, reset inner wiretension. Shift to innermostchainring and loosen inner wirepinch bolt. Pull the wire withfourth-hand tool and tightenpinch bolt. Begin adjustment ofinner wire tension as above.

6. Test shift of front derailleur toboth front chainrings.

Front DerailleurPerformance

The front derailleur should shift thechain between chainrings withoutthrowing the chain off the extremeouter and inner rings. It is possiblethat the front derailleur will rub thechain slightly even on properlyadjusted bikes. This is likely onsome bikes when riding in thelargest sprocket in front and thesmallest cog in back. As the bike ispedaled with force the frame flexesand moves the chainrings side toside, which cause an intermittentrubbing noise. Loosening the H-limitwould move the front cage outmore, and may stop the rubbing,but it may also cause the chain to

shift over the largest ring and comeoff. If all aspects of front derailleuradjustments are correct on thisbike, the rider is simply exceedingthe engineering and designcapabilities of the machine.

Rear DeraillerAdjustments (derailleur)Rear DerailleurAdjustmentTypical Tools and Supplies Needed:

Repair Stand, PRS and PCS stands.

Screwdriver, Phillips #2 or straightblade

Hex Wrenches, if changing inner-wire AWS series.

Light lubricant

Forth Hand Tool BT-2

Cable cutter, if trimming cable CN-

10

Rags

The article will discuss theadjustment of the rear derailleur.See also related articles:

Derailleur bicycles have severalsprockets on the rear hub. By usingdifferent combinations, the rider willfind low gears for going up hill andhigh gears for going down hill. Thegear system needs maintenanceand adjustment to perform well.The cable system may also needreplacement as it wears. Thederailleur limit screws and indexsetting will need periodic checking.

This article will first discuss limitscrew setting, and then indexadjustments.

Derailleur Limit Screws(H-Screw and L-Screw)Rear derailleurs "derail" the chainfrom one sprocket and move it toanother. The upper derailleur pulley(called the "guide pulley" or G-pulley) pushes the chain to the nextsprocket. A proper gear adjustmentaligns the guide pulley under theintended sprocket.

Changes to the inner wire tensioncauses movement in the derailleur.The derailleur body is fitted with a

spring that is pulled tight, orrelaxed, by the inner wire. Pullingthe inner wire moves the derailleurcage and guide pulley in onedirection and tightens the spring.Relaxing inner wire tension allowsthe spring to move the body andpulley in the opposite direction.

It is normal for a chain to makesome noise during a shift. The shiftmay appear subjectively "noisy,""loud," or "rough". Factors like thetype of chain or sprocket, the wearon each, and the amount and typeof lubrication will affect the noise achain makes during shifting. Thelimit screws typically can do nothing

to affect the noise during a shiftbetween cogs. Noise from the chainas it rides on the sprocket is,however, a useful symptom. Thereis for any given bike a "base level"of noise from the chain as it passesover the sprocket teeth. When thederailleur jockey wheel is out ofalignment, the chain may makeexcessive noise. To demonstratethe "base level" noise, shift the biketo the second sprocket by pullingthe inner wire. Continue to pedaland move the inner wire slightly tohear changes in the level of noise.The quietest level of noise may beconsidered the base level for that

bike.

Derailleur pulleys are limited inboth inward and outward motionsby using the derailleur limit screws.Properly set, the derailleur will shiftto both the extreme outwardsprocket (the smallest in size) andthe extreme innermost sprocket(the largest in size). The limitscrews do not control the derailleuron the sprockets between the twoextremes. These are set using thebarrel adjuster and tension on theinner wire. The limit screws areusually marked "H" and "L". The"H" controls the outer most limit ofthe derailleur, and the "L" controls

the inner most limit.

Using the shift lever to adjust limitscrews can cause confusion andproblems because it tends to focusattention on the inner wire tension(indexing) rather than limit screwsettings. Instead of using the shiftlever, pull the inner wire with one

hand to simulate shift lever action.This will help eliminate confusionbetween indexing problems andlimit screw problems. With the bikein a stand, practice shifting with thismethod before adjusting the limitscrews.

Turning the limit screws adjusts the

limit of travel of the pulleys.Tightening restricts the travel, whileloosening allows more travel. Thepurpose of the following procedureis to find the tightest H-limit screwsetting that will allow a good shiftto the outermost cog, and thetightest L-screw setting that willallow a good shift to the innermostcog. The location of limit screws onthe derailleur body may varybetween manufacturers. Alwayslook for the "H" and "L" markedadjacent to the screws.

H-Limit Screw Shift chain to outermost

(largest) chainring. Shift chainto outermost rear sprocket(smallest sprocket).

Check tension on rear inner wire.If inner wire appears to haveany tension, it may interferewith the H-screw setting. Turnadjusting-barrel clockwise toeliminate inner wire tension.Proper cable tension (indexing)will be adjusted later.

Pedal bike at a quick cadence,approximately 60 rpm or more.

Pull inner wire to shift derailleurone sprocket inward. Adjust pullon inner wire until chain rides

quietly on second sprocket.Release inner wire quickly toshift back to outermost sprocketand note shift. When adjustingthe H-screw, be concerned withtwo situations:

1. The outward shift from thesecond sprocket to theoutermost sprocket.

2. How the chain rides on theoutermost sprocket.

3. Do not be concerned withhow the chain rides when itis held on the secondsprocket.

4. If the shift outward seems

acceptable, tighten H-screw1/4 turn clockwise and repeatshift. Even if shift appearsacceptable, continuetightening H-screw by 1/4turn increments and checkingshift until shifting is slow orhesitant. Another symptom ofa too tight H-limit screw iswhen the chain is on thesmallest cog but makes arattle from rubbing thesecond sprocket inward. Viewthis last symptom by lookingunder the rear sprocketswhere the chain meets thesprockets. The inner plate of

the chain will rub against thenext sprocket inward makingthe noise.

5. When symptoms of a tootight H-screw appear, loosenH-screw 1/4 turn and checkshift again. Repeat process ofshifting and correcting by 1/4turn increments. When tootight symptoms disappear, H-screw is at tightestacceptable setting, and limitscrew setting is done.

NOTE: "Rapid Rise" or "Low-Normal" derailleurs use a reversespring application. When the innerwire tension is completely relaxed,the derailleur sits on the inner mostsprocket, which is reversed fromother common derailleurs. Whenadjusting the H-limit screw, it is

necessary to pull the inner wireuntil the chain is in the second tooutermost sprocket then pull hardto shift to the outermost sprocket.The same concept is used to adjustthe Shimano® "Rapid-Rise" or"Low-Normal" derailleurs. You wantthe tightest limit screw setting thatallows good shifting to the extremeouter and inner cogs.

L-Limit ScrewThe L-limit stops the derailleur frommoving inward (toward the spokes).The limit screw does not make thederailleur move, pulling the innerwire makes the derailleur move.

The L-screw allows the pulleywheels to shift the chain to theinnermost sprocket and yet not shiftoff the sprocket into the spokes.

1. Shift bike to middle chainring (orsmaller ring of double chainringbikes) and to second-to-innermost rear sprocket.

2. Pedal bike at a quick cadence,approximately 60 rpm or more.

3. Pull inner wire by hand to shiftderailleur sprocket inward. Whenadjusting the L-screw, beconcerned with two situations:

1. The inward shift from thesecond-to-innermost sprocket

to the innermost sprocket.

2. How the chain rides on theinnermost sprocket.

3. If shifting seems adequate,tighten L-screw 1/4 turn, andrepeat shift. Continue totighten L-screw untilsymptoms of too tight appear.These symptoms are that thechain will not complete shifteven with pressure on innerwire, the chain hesitatesbefore shifting inward evenwith constant pressure oninner wire, or the chain rattlesexcessively when riding oninnermost sprocket

4. When symptoms of a tootight L-screw appear, loosenL-screw 1/4 turn and checkshift again. Repeat process ofshifting and correcting by 1/4turns. When too tightsymptoms disappear, L-screwis at tightest acceptablesetting, and limit screwsetting is done.

B-Screw AdjustmentAfter setting the L-screw, check the"B-screw" for an adequate setting.The B-screw controls the derailleurbody angle, hence the name, B-screw. Shift to the innermost rearcog, which is the largest cog. Viewthe upper pulley relative to the

largest cog. If the pulley is rubbingagainst this cog, tighten the B-screw to increase upper pivot springtension, which pulls the pulley backand away from the cog. If there is alarge gap between the upper pulleyand cog, loosen the screw. To find agood setting, loosen the B-screwuntil the upper pulley begins to rub,then tighten the screw to getclearance.

Check for rubbing of largestsprocket and upper pulley

Change B-screw as necessary

Campagnolo®Some Campagnolo® modelderailleurs have a body tensionadjustment at the pulley cage, notat the upper pivot. The screw isbasically a "rack and pinonquot;system. The cage spring platerotates to increase or decreasetension. The upper pivot and lowercage pivot springs oppose oneanother. In this system, the upperspring is fixed. Increasing cagetension (turning screw clockwise)will bring the upper pulley closer tothe cog. Decreasing cage tension(turning screw counter-clockwise)

will increase the distane betweenupper pulley and cog.

SRAM® DerailleursSram® designates a 6mm betweenthe largest rear cog and the upperpulley. Use a 6mm hex wrench tohelp estimate this gap.

NOTE: Shimano "Rapid rise" or"Low-Normal" Shimano® "Rapidrise" derailleurs or "Low-Normal"reverse the spring direction fromconventional derailleurs. Thederailleur moves inward (towardthe spokes) when the cable tensionin relaxed, or or "normal" position.To adjust L-screw, pull on innerwire and shift outward onesprocket, then release inner wire toshift inward. Tighten L-screw untilshifting is slow, then turn counter-clockwise 1/4 turn until goodshifting is restored.

The process above sets the limits tothe tightest setting that still shifts

well. This allows the derailleur towear with use and time, and yetstill allow a good setting. After limitscrews are set, proceed to indexadjustments.

Checking the RearIndexing AdjustmentThe rear indexing adjustmentshould only be done after the H-limit and L-limit screws areadjusted. The rear derailleurindexing is adjusted by changingthe inner wire tension. For thecommon rear derailleurs, increasinginner wire tension tends to movethe rear derailleur more to the left,

or toward the spokes. Less innerwire tension tends to move thederailleur to the right. The innerwire tension will not stop thederailleur at its extreme limits. TheH-limit screw stops the derailleur atits right most setting, and the L-limit screw stops the derailleur atits left most setting. (Shimano® or"Low-Normal" derailleur are a bitdifferent, see procedures at thebottom.)

Modern indexing shift levers usedwell, which is a hesitationbetween movements in the lever.These hesitations are timed tomatch the movements of the

derailleur and the spacing in therear sprockets. The design of somederailleur and shift lever brandsrequires more of a push (or twist)of the lever to complete the shift.The amount of extra push or twistis not consistent betweenmanufacturers and each rider mustlearn the particular attributes of hisor her system.

Changes to inner wire tension aremade at the adjusting barrel.Adjusting barrels may be locatedeither at the rear derailleur or atthe shift lever. The goal ofadjusting the indexing is to find thetightest inner wire tension setting

that will allow good shifting to thegears normally used. This will allowthe longest lasting indexingadjustment as the system wearsand the cable system stretches withuse. To find the tightest inner wiresetting, you will purposely make thesetting too tight then relax tensionslightly. There are two basicsymptoms for a "too tight" innerwire. These are a rattling noisefrom the chain rubbing against thenext cog inward, and a slow orhesitant outward shift. These aresymptoms for rear derailleurs thatsit outward when inner wire tensionis released.

NOTE: If the cable inner wire is notcorrectly routed into the derailleurpinch bolt, a good indexing settingmay not be possible. The wireshould leave the barrel adjuster andtravel straight to the pinchmechanism. The upper image iscorrectly routed, while the lowerimage shows incorrect routing.

Index Setting1. Set limit screws (if not already

done).

2. Shift chain to outermost rear

sprocket (smallest). Shift chainto outermost (largest)chainring in front.

3. Test initial inner wire tension.Pedal a normal cadence andshift rear derailleur with oneclick on lever. Use care to onlymove lever one position. Ifderailleur moves one sprocket,tension is adequate.

4. If derailleur fails to shift onesprocket, inner wire may be tooslack. Turn barrel adjuster fullyinto derailleur body (or shiftlever) then turn counterclockwise two turns to allow forindex adjustments. Loosen

inner wire pinch bolt and gentlypull on inner wire with fourthhand tool or pliers to removeslack. Tighten inner wire pinchbolt.

5. If derailleur will not shift onesprocket after removing slackin "d", return lever back tooutermost sprocket positionand increase inner wire tensionby turning barrel adjustercounter-clockwise 1/4 turn andattempt shift again.

6. Shift to second sprocket in rear.Pedal and increase inner wiretension by continuing to turnadjusting barrel counter-

clockwise until a definiterattling is heard. Rattle is fromchain scrapping against nextsprocket.

7. Once a too-tight rattle isachieved, turn barrel adjuster1/4 turn clockwise, to releaseinner wire tension, and pedalagain. Listen and look for signsof scraping or rattling. Continueturning barrel adjuster 1/4 turnclockwise at a time until rattledisappears.

8. Shift derailleur one sprocketinward at a time, listening forsigns of rattle, indicating a tootight inner wire. Turn adjusting

barrel 1/4 turn clockwise toeliminate rattle. Note: Do notattempt shift to largest rearsprocket while in largest frontsprocket. This gear is normallynot used and adjusting tensionto this shift may compromiseother commonly used gears.

9. Shift to innermost (smallest)chainring and check gearsagain. If no rattling is present,index adjustment is done.

Shimano "Rapid Rise" or"Low-Normal"Derailleur IndexingAdjustment

Shimano "rapid rise" or "Low-Normal" derailleurs use a returnspring that puts the derailleur underthe innermost rear sprocket whenthe inner wire tension is released.As with other indexing derailleurs,the inner wire tension should be setas tight as possible with goodshifting. However, the symptoms ofa too-tight setting are different,which for "Low-Normal" systems arewhen the derailleur shifts outwardslowly, or a there is a rattle fromthe upper pulley being aligned toofar outward. Look underneath therear sprocket at the alignment ofthe upper pulley when there is a

rattle to see if this is the cause.

1. Shift chain to middle ring infront and innermost sprocket inback.

2. Pedal and shift lever oneposition.

3. Pedal and turn barrel adjustercounter-clockwise to tighteninner wire tension until chainbegins to shift outward.

4. Turn barrel adjuster clockwise1/4 turn until chain runssmoothly on second cog.

5. Shift outward one sprocket at atime trying each gear. Turnbarrel adjuster 1/4 turn

clockwise if too tight symptomsoccur.

6. Shift to all other normal gearcombinations and testadjustment.

NOTE: The indexing procedure hereassumes that there are no unusualproblems, such as bent derailleurs,bent derailleur hangers or excessinner wire friction from dirt in thehousing. Additionally,manufacturers design shift leversand drive train components to workwithin their system. Mixing brandswithin the drive train may lead topoor shifting. This is referred to asan compatibility problem.

Rear DerailleurOverhaulRear DerailleurOverhaul and PulleyCage TensionTypical Tools and Supplies Needed:

Hex wrenches

Screw drivers, narrow straightblade and #2 Phillips

Work tray for small parts

Seal pick (optional)

Bench vise (optional)

Grease: Park PolyLube®

Degreaser for cleaning smallparts CB-2

Light lubricant such as CL-1Chain Lube

This article will discuss the overhaulof rear derailleurs.

Some rear derailleur models allowthe internal servicing in order toclean and lubricate. This oftenimproves performance by removingdirt from pivots. Additionally, somemodels allow for the changes to thepulley cage tension spring. Thereare also after-market top pivot"break-away" bolts, which may be

installed in place of the originalmounting bolt.

Derailleur WearThe rear derailleur will becomeworn with use and abuse. As thederailleur wears, it will develop playat all pivot points. Grab the cage atthe lower pulley of a new derailleurwhile mounted to a bike and wiggleit side to side. Do the same test onan old model to compare. Replacederailleur when this play becomessignificant.

The derailleur pulleys will wear andeventually require replacement.The teeth will thin and becomepointed, especially the lower pulley.Worn pulleys will not be able tohold or guide the chain as well asnewer pulleys, and shiftingperformance will suffer. In the

image below, three pulleys areshown in progression of wear.Pulley bearings or bushings will alsowear and create more play in thepulley.

Derailleur Service

It will be useful to have a note padand pen to help you remembercorrect orientation of parts. Sketchany parts that seem unfamiliar, oruse a digital camera for the same

purpose. Have some wire ties ortwine on hand to help tie parts intheir correct orientation as theycome apart.

Begin by removing the rearderailleur from the bike. For bicyclechains with no master-link, the cagemay be dismantled, which allowsthe chain to stay together.

Note and record any markingdistinguishing upper and lowerpulley. Also note the orientation ofthe cage. Loosen and remove bothderailleur pulley bolts. Remove thecage and chain from the derailleur.

Shimano® Derailleur

OverhaulShimano uses a tension spring inthe upper pivot, at the mountingbolt. The pulley cage also uses aspring. The two springs opposeeach other. Changes in springtension will cause the body of thederailleur to rotate, causingchanges of upper pulley relative tothe larges cog. Increasing thetension of the pulley cage willrequire increasing tension in theupper pivot. If the upper pivot B-screw adjustment is already as tightas possible, do not change tensionin the pulley cage to a highertension setting.

The procedure for derailleuroverhaul is as follows:

1. Use a thin tipped screwdriver topry off the C-clip on the backside of the derailleur mountingbolt. Work over a table to avoidloosing parts. Maintainpressure on the B-screw plateagainst the body whileremoving the clip. This helpsprevent parts from flying off asspring tension is released.

2. Remove body-screw plate fromderailleur body. Note and writedown orientation of parts. Noteespecially any seals and thedirection of seal lips.

3. Remove the lower cage fromthe derailleur body. There areseveral different systems ofcage attachment. Many modelsfrom Shimano® use a screwunder the body, called the P-screw. This screw holds a studmounted to the pulley cage. To

prevent premature release ofcage spring tension, holdderailleur cage firmly toderailleur body and remove thisscrew using hex wrench.

4. Alternatively, there may be aset screw in the derailleur cagethat acts as a stop. Pivot cage

away from stop, and removeset screw, then allow derailleurto unwind. Note direction cageunwinds for re-assembly.

For P-screw type derailleurs,hold both derailleur body andderailleur cage. Pull cage awayfrom body and allow cage to

unwind. Note direction thecage unwinds.

5. The derailleur cage may beheld to the body with a pivotbolt. The bolt head may facetoward outside, away from thespokes, or it may face inside,

facing the spokes. Loosen andremove bolt. Note and recordany washers or seals found onbolt or on cage.

6. As cage is removed from body,make note of the spring hole inthe derailleur cage and body.There are commonly two or

more hole choices. Newderailleurs are typicallyassembled with the spring inthe hole that allows the mostrelaxed position of the spring.If more cage tension is desired,the spring end can be installedin the other hole.

7. Remove spring from insidederailleur body. Note especiallythe direction of the coil ends.The smaller end tends to facetoward the derailleur cage, andthe larger end goes into thederailleur body. There is

commonly a seal as well. Notedirection of lip.

8. If derailleur cage is stilltogether, loosen and removeone at a time each pulley bolt.It is common for the upper andlower pulleys to be different.Do not mix parts from upper

and lower pulleys. Upper pulleymay be labeled as "G" pulley,or simply "upper".

9. Note parts orientation of coverplates, seals, and bushing. Usea wire or string to tie theseparts together in the correctorientation.

10. Some pulley have have acartridge type bearing. Use aseal pick to carefully lift theseal from the inside edge.

11. Clean all parts is a degreaseand dry. Use compressed air ifpossible, but do not allowbearings to spin.

12. Use a light lubricant on pulleybushings and seals. Assemblepulleys into cage in the same

orientation as they weredisassembled. Remember torefer to your notes onorientation. Install and tightenpulley bolts to about 30 inch-pounds. Use of a mild threadlocker is recommended.

13. Cover both springs heavilywith grease.

14. Install cage spring intoderailleur body, with smallertapered end of spring facingoutward toward cage. Be sureto engage spring into springhole inside body. Place dustseal over derailleur body as itcame off.

15. Engage cage spring intoderailleur cage and body. Againrefer to notes fromdisassembly. Changing springhole location will changetension. In the image below,spring is in most relaxedposition. Seen from thisorientation, cage will berotated counter-clockwise forworking tension.

16. In the image below, the springis engaged in the highertension spring. Notice cagemust now be wind furthercounter-clockwise, adding to

spring tension.

17. Press cage into derailleur bodyand begin to rotate derailleurcage toward back of derailleur.It is important to always wrapthe spring tighter in the samedirection as the coil.

18. Looking at the back side of thederailleur (opposite side ofbrand name) rotate cageclockwise to tension spring.

19. For P-screw type derailleurs,cage stop and derailleur bodystop must clear. Pull slightlyoutward on cage and allow thetwo stops to pass. Push cagefully into derailleur body oncestops are cleared.

20. For bolt type pivots, rotatecage until you can access stopscrew.

21. For P-screw type, re-install setscrew into derailleur body.

22. Mounting bolt spring can bedifficult to engage and tension.It is useful to mount a hexwrench with the short "L"facing upward in a vise. Thevise and wrench act as a holderand frees up your hands.

23. Install spring into body insame orientation as it cameapart. Note direction of springcoils, which will indicate thedirection of tensioning spring.Place dust seal over spring.Engage body tension plate onspring. Press plate fully downto see if plate will fully engagesystem.

24. Using needle nose pliers, grabbody angle screw.

25. Again, tension spring withdirection of wrap. Upper pivotsprings wrap counter-clockwise.Rotate plate counter-clockwiseto tension spring. Pull plateupward enough to clear stoptabs on each.

26. Push downward on plate andhold pressure downward beforeinstalling C-clip.

27. Install C-clip onto mountingbolt. Use needle nose pliers tofully engage C-clip.

CAMPAGNOLO

The Campagnolo derailleurs sharemany service features of theShimano derailleurs. Both upperand lower pivots have a spring. Thederailleur is fully serviceable.

1. Remove C-clip from upperpivot. Use screw driver andsame procedure as described inShimano above. Note hole inplate that holds spring end.

2. Remove both pulley wheel boltsand inner pulley cage.

3. Loosen cage pivot bolt. Usecare and proceed slowly ascage will unwind as it clearscage stop.

4. Remove spring from derailleurbody.

5. Clean all parts.

Assembly

1. Grease all springs.

2. Install the shorter spring in theupper pivot. Select the correctspring hole in the plate. Onehole will require the plate bewrapped more and thisincreases upper pivot tension.This would result in pulling thederailleur back and away from

the cogs.

3. It can be useful to mount a hexwrench in a vise to hold thederailleur body and bolt. Rotatethe place counter-clockwiseand press downward to engageplate stop against body stop.Engage C-clip using needlenose pliers.

4. Install lower pivot spring intoderailleur. Insert bolt throughcage and place spacer at end.

5. Insert cage and bolt intoderailleur body. Insert springinto cage spring hole.

6. Rotate cage to tension spring.

7. Push cage to body once itpasses cage stop. Carefullythread bolt and secure.

8. Install both pulley bolts. Theupper pulley is marked "upper."Use a mild thread locker on thepulley bolts.

SRAM® X.0 Derailleurs

The X.0 derailleur may beoverhauled at the lower cage pivot.The mounting bolt has no spring,and it is best to leave this bolt inplace. No lubrication of themounting bolt pivot isrecommended.

The SRAM® parallelogram spring isvery strong. It is possible to use azip tie to hold the derailleur bodyaway from the cage, making iteasier to work with the cage. Feeda zip tie through the body belowthe cable stop, and through thecable guide. Pull the cage awayfrom the body as if shifting toward

larger cogs, and secure the zip tieto hold the body.

Lower Pivot OverhaulProcedure

1. Rotate cage to expose the cagestop screw. Loosen and remove

the stop screw. Cage will nowrotate back past the stop screwposition.

2. Allow cage to rotate forwardand relieve spring tension.

Note position of cage toderailleur body in this relaxedposition.

3. The pulley cage is held to thebody with a stud pressed intothe cage. The stud has a "D-fitting", that mates with a D-shape recess in the body. Thebody must be rotated to oneposition only before the cagecan be removed.

4. There are three tension optionsin the cage, as seen in imageabove. The middle spring holeis used on new derailleurs. Todecrease chain slap, increase

spring tension by moving springto left hole of the threechoices, as seen from the studside.

5. After removing the pulley cage,loosen and remove pulleybolts. Pulleys use a cartridgebearing, use care whenremoving seal.

6. Clean all parts in a degreaser.Pack grease into seals ofpulleys and re-install seals.Pack grease into cage pivotspring.

7. Assemble pulley wheels intocage and install pulley bolts. Amild thread locker is

recommended on the threads.Spin pulleys to check proper foralignment after securing bolts.

8. Place spring into body ofderailleur in same orientationas it was removed. Engagespring end into desired cagehole.

9. Push cage to derailleur body.Cage must rotate to allow "D"fitting to engage into body.Approximate position of cageto body for "D" fittingalignment is shown below.

10. Rotate cage counter-clockwiseas seen from orientation ofimage above. Install andsecure cage stop screw.Remove zip tie. Derailleur is

ready to be installed.

Mavic® MektronicThe Mavic® Mektronic derailleurhas many internal parts, includingelectronic parts. There are very fewuser serviceable parts. The pulleywheels can be brushed clean with adry bush. Avoid using solventsduring cleaning.

There is a boot covering the armthat extends to shift the pulleycage. Use only a soapy water on arag to wipe this clean. Use care notget water or soap into the workingmechanism.

The derailleur uses a solenoidinitiate the shift. It is activated by abattery. The battery cover isremoved using a 1-Euro coin(substitute US twenty-five centpiece).

The derailleur B-screw is located atthe top mounting bolt. There is aspring in this pivot, but it isrecommend the pivot not bedismantled.

SRAM FORCE and RIVAL

The SRAM Force and Rival rearderailleur use an upper pivot boltthat has no internal spring. It maymay be cleaned and lubricatedwithout disassembly. The pulleysmay be removed for cleaning. The

lower cage pivot the should not betaken apart.

Remove pulley bolts using a hexwrench.

Pulleys and cage plate of SRAMForce derailleur.

Cutting Cable HousingThis article will discuss the cuttingand sizing of both brake andderailleur housing. See also relatedarticle Brake and Shift levers.

Typical Tools and Supplies:

Cable Cutter: CN-10

Brake housing and cables asneeded

Shift housing (compressionless)and cables as needed

Housing end caps (ferrules) asneeded

Light lubricant

Mill file (for brake housing asneeded). Bench grinder ordermel also useable.

Hex wrenches for cable binderbolts

The Park Tool CN-10 is designed tocut multi-strand wires such as gearand brake cable, brake housing,and compressionless gear housing.Compressionless shift housing usesmany inner support wires runninglongitudinally with the inner plasticliner. Compressionless shift housingis intended for shifting systemsonly, not braking. Brake housing ismade of a wire wound around aplastic liner. Use ends caps or

ferules at the ends of housing whenever possible. It is recommended tolubricate inside the housing or thecable is installed.

The jaws of the cable cuttersurround and then sheer thematerial. Using plain diagonalcutters can simply flatten and

smash cables. As with all cuttingtools, it is recommended to weareye protection.

Grab and hold the cable or housingclose to the jaws. Use care not tocut your fingers. Hold cable orhousing perpendicular to jaws andsqueeze levers quickly for a cleancut, as seen below.

After cutting the compressionlessgear housing, inspect the end tosee if it flattened a bit. Use thecrimper section of the CN-10 or CN-4 to open up the housing and innerliner before installing an end capand cable. You can also use the

crimper section cutter to crimp on acable end cap, as seen below.

How Long ShouldHousing Be?Brake and gear housing allows thecable wire to be routed aroundbends and connects the levers tothe frame stops. The less the dragon the cables, the better for theshifting and braking. Too short ofhousing will cause it to kink andbind, making even more friction. Asa rule of thumb, try to size thehousing so it is as short as possiblebut it still enters the stops andbarrel adjusters in a straight

approach. For the rear derailleurhousing, note especially how thehousing enters the barrel adjuster.

In the image above, the housingbends immediately upon leavingthe barrel adjuster. This canactually bend the housing end cap.The image to the right shows howlonger housing in this case allowsthe housing to enter straight.

The image above is a typical newbike housing length. The housingbends and kinks as it enters thebarrel adjuster. The image to theright shows longer housing allowinga straight entry into the barreladjuster.

The image above shows brake andshift housing which is much toolong. The housing could beshortened and still have a smooth,straight approach to the levers andhousing stops.

The routing of housing may affectthe length. Typically the front

derailleur shift housing is run on theleft side of the frame, while the rearderailleur shift housing is run on theright. This may at time causeunnecessary bending in thehousing. In some cases, it ispossible to "cross over" thehousing, running the front shifter tothe right side stop, and the rearshifter to the left side stop. It willthen be necessary to again crossthe cable. Consider this option, butif the cable ends up rubbing theframe, it is not a good idea. Theremay be some light rubbing betweencables, but this would result in lessfriction than poorly routed housing.

Shift lever housing that is too long.Housing passes center line of bike,then must bend back to housingstops.

Shift housing is crossed over atheadtube, and crossed again ondowntube. Arc of housing is muchsmoother than black housing inexample of too long housing.

Cutting Brake HousingBrake housing is typically made ofsingle strand flat wire wrapped

around an inner plastic tube. Thishousing may be cut with the CN-10,CN-4, or diagonal pliers. Because ofthe design of the housing wire, it isnot always possible to get a flat,clean cut. It is best to finish anyburr with a file. Lightly grinding theend will also improve the housingand reduce friction. NOTE:Compressionless housing does notrequire finishing.

Adjustment of the CN-4As a cable cutter wears, it mayrequire readjustment for bestcutting results. Grab the handles

and wiggle them against the axis ofthe thread. If there is play betweenhandles, turn locknutcounterclockwise to loosen nut, turnbolt head clockwise slightly totighten adjustment, and retightenlocknut. Repeat adjustments asneeded until tool cuts cable cleanly.If handles bind, turn locknutcounterclockwise to loosen nut, turnbolt head counterclockwise slightlyto tighten adjustment, thenretighten locking nut. Repeatadjustments as needed until toolcuts cable cleanly.

Shift Levers (shifters)Useful Tools andSuppliesThis article will discuss the shiftwire (cable) installation. See alsorelated article discussing housinglength.

SRAM® Shift Levers

SRAM® shift levers are commonlycalled Grip-Shift. The levers mountto the handlebar between the brakelevers and the grips. The lever maybe rotated on the bar so the cablehousing exits without interference.

There have been different

generations of the Grip-Shift levers,and wire installation of the shiftwire can vary. Inspect the lever anaccess hole or cover. Shift the leverto the most relaxed wire position.Remove the cover. Disconnect thewire from the derailleur. Pullhousing away from lever and pushbare wire to remove wire fromlever.

Remove cover to expose wire end.

Some models may have a small setscrew over the wire end. Use a hexwrench to remove this screw.

Remove set screw.

On some SRAM® models the wireend may be held in the lever by asmall clip. Usea small screwdriverto pry back this clip, and then pushthe wire end out.

Pry clip back to access wire end.

Feed the wire in and out through

access hole.

Shimano® STI ShiftLeversShimano® levers have haddifferent generations that vary inwire attachment. There may be acover on the lever body that mustbe removed. There are both pry-outtype covers and threaded typecovers. Remove cover, if any. Shiftthe lever to the most relaxed cableposition. Detach wire fromderailleur. Pull housing away fromlever and push the wire outwardfrom the lever.

XTR® and XT® levers may alsohave a cover plate. Use a #1 or #0cross tipped (Phillps) screwdriver toremove two screws. The screws arequite small, so use care whenremoving. It is helpful to rotate thebike upside down until the screwheads are pointing upward.

The wire end is held in a fitting thatallows easy removal. There is a slotin the adjusting barrel and thebody. Rotate the adjusting barrel sothe slots align, and lift the wireoutward. Install new wire intofiting, and into adjusting barrel.Install cover plate and screws.Tighten screws until snug, but donot over tighten.

Shimano® XTR Rapid RiseIntegrated Shifter

The integrated rapid rise shifteruses a cover that must be removed.Use a small cross tip (Phillips)screwdriver to remove the smallscrew holding the cable cover.

Remove cable cover screw.

It is not necesary to remove anyother screw, remove only on thecover screw.

Push gently but firmly outward oncable cover.

The cover plate may be a snug fit.

Push outward only, do not plyforward to remove.

The shift wire head sits inside acarrier. Articluate the shift lever togain access to the wire end, and pryup and out. Install a new wire.

Replace cable cover by sliding itinto place. Replace cable coverscrew.

Shimano® Revo ShifterThe Revo Shifter is a twist typeshifter. The lever must be partlydismantled to remove the shiftwire. The lever is secured to thehandlebar with a clamping screw

under the lever.

The Revo Shifter

Shift the lever so the cable is in themost relaxed position. Rotate thelever toward the front, as seen fromthe rider"™s point of view. Detatchthe cable from the derailleur andpull the housing from the leverbody.

There is small screw holding thecable cover to the lever body. Thescrew is located on top of theshifter body toward the front of thebike. It will be inboard of thetwisting part of the lever. Use asmall Phillips screwdriver such asthe SD-0 to remove.

Remove cover screw.

The cover is plastic, use care, anddo nothing drastic. The front of thecover will be free to lift, but do notpull up of the front at this time, itmay break the cover. The rear ofthe cover is held by an internal bossfitted to the lever body. Pry with ablade or narrow tool at the back ofthe lever at the split. Lift the backof the cover upward.

Pry at back of cover to remove.

Lever is removed to expose cableend.

Use a small pointed tool to bendcable head out of socket in lever.Pull old wire and remove it fromlever. Install new wire into leverfitting and through wire routing inlever body. Inspect that wire

follows routing before installingcover and securing cover screw.

Drop Bar IntergrtedBrake-Shift LeverDerailleur WireInstallationThe derailleur wire end attaches to

the shift lever by fitting through asmall socket called the derailleurwire anchor pivot. The wire anchorpivot is sometimes difficult to see.Begin by shifting to the most leverrelaxed wire position. Feed the cutend of the wire through the anchorpivot, and pull it fully through unitthe head engages the pivot.

Derailleur wire attachment is on theoutside of each Shimano® STI roadlever.

Campangolo® derailleur wiresaccess from the underside of thelever body.

Shimano 7900 LeversShift cable feeds from underneaththe lever. Pull rubber cover forwardto expose cable access hole on the

outer edge of each lever. Shift smalllever several times to move thecable anchor socket to the correctposition.

Shift cable installs from under the

lever body

Feed cable end through cableanchor and out the top of thelever. Shift cable exit has twooptions. One option routes housingto the front side of the handlebar .The other option is the outergroove which routes housing to thebackside of the handlebars. Thebrake cable exits from the innerhole.

The thinner shift wire is routed fromthe inner groove option. The thickerbrake wire is routed from the brakehole.

Chain LineTypical Tools andSupplies: Repair Stand, holds bike secure

for easy work.

CLG-2 chainline gauge(discontinued)

Caliper and feeler gauges

This article with discuss the use ofthe CLG-2 chainline Gauge and theconcept of chainline. Also seerelated article on frame alignment.

Chainline and ShiftingIssues

There are two related aspects tothe term "chainline". First, chainlinecan be defined as the position ofthe cogs or chainrings relative tothe center line of the bike. The bikecenter line is an imaginary planerunning front to rear through themiddle of the bike. For example, afront crankset and/or frontderailleur might be desgined tohave a chainline of 47.5mm. Thismeans it will work best when themiddle of the crankset is 47.5mmfrom the middle to the bike centerline.

Chainline can also refer to therelative position of the front and

rear cogs to each other, withoutregard to the bike centerline. This iscalled "effective chainline". A bikemay have the crankset inward oroutward some distance of the rearcogset center.

Drive train manufacturers do notgenerally specify "perfect" orcenter-to-center alignment betweenrear and front cogsets. The frontchainrings may be a few millimetersoutward relative of the rear cogs.Additionally, drive trainmanufacturers do not generallyconsider all gear combinations to be"useable". For example, a so-called"27-speed" bike has three rings in

front and 9 cogs in the rear.However, it is likely when the chainis on the smallest cog in front andpossibly 2 or 3 of the smallest cogin back, the chain will rub the sideof the middle ring. This should notnecessarily be considered a"chainline" error. If this bottombracket length were increased untilthere was not rubbing in thesecombinations, there may be poorshifting in other gear combinations,such as the largest ring and thelarger rear cogs. Thesecombinations are commonly called"cross-chaining". Bicycle chains arequite flexible, and will work well at

various other then perfectlystraight. Cross-chaining is primarilyan issue when the chain hits thefront rings. As a simple rule, if agear combination causes a rubbingproblem, avoid that gear.

Rear Cogs to FrontRings- EffectiveChainlineThe CLG-2 Chain Line Gauge helpsdetermine effective chainline of thefront and rear gears. The toolreferences off the rear sprocketcenter and extends this line forwardtoward the front rings.

To use the CLG-2, begin bychecking the centering of rearwheel in frame. It should becentered between chain stays.Begin by getting the chain out ofthe way. Shift chain to smallestfreewheel cog, and the innermostchainring (smallest ring). It issometimes necessary to drop thechain off the front chainring ontothe bottom bracket so it does notstrike to CLG-2.

For odd numbered rear cogs (5,7,9-speeds), clamp the CLG-2 overmiddle cog. Snug the knob and donot over tighten.

For even numbered rear cogs(6,8,10-speed), the middle offreewheel is a space, with the samenumber of cogs on either side.Clamp the CLG-2 so the main bar is

falling in the middle space. The toolwill clamp the cog inboard of thismiddle space (4th cog of 6 speeds,5th cog of 8 speeds, 6th cog of 10speeds.) Snug knob and do not overtighten.

Extend sliding gauge close tochainring, but do not allow contactwith chainrings or the frontderailleur. Most freewheels andfreehubs have play. After clamping

gauge, move CLG-2 end side toside, and hold end to center of playfor most accurate reading.

Reading the CLG-2Odd Numbered CogsBecause the CLG-2 clamps over thecenter cog of odd-numberedfreewheel (5, 7, 9), the black slidinggauge represents the middle of therear cog set. The center of slidinggauge may or may not point tocenter of chainring set. If the slidinggauge is not pointing to the middleof the front crankset, estimate theamount to either side it is off.

NOTE: Most component

manufacturers do not design drivetrains for "perfect" or center-to-center alignment. It is common forthe chainrings to be slightlyoutward of the rear cog chainline byas much as several millimeters.

Even Numbered Cog SetsFor even numbered rear cog sets

the CLG-2 clamps over the coginboard of the cog set center. Themain chrome arm, not the blacksliding gauge represents the rearcog set center. It is thereforenecessary to estimate the centerwhere the end of the gauge pointsat the front chainrings.

For three ring cranksets, the slidinggauge should point inboard, or justto the left from the rider"™s pointof view, of the middle ring.

For double ring cranksets, the black

sliding gauge should point justoutboard, to the right, of the innerring.

Front Chainring Positionand Bottom BracketLengthThe front chainrings should to bewithin a certain distance of thebicycle center line. If the rings aretoo far in or too far out from theframe, the front derilleur may notshifting properly. The position of

the front rings is in large partdetermined by the length of thebottom bracket spindle. Manybottom bracket spindles arespecified with a certain chainlinenumber, such as 47.5mm or 50mm.Spindles are also specified byspindle length, which is simply thelength end-to-end. As an example,a particular bottom bracket may bespecified wtih a 47.5mm chainline,and a 113 spindle length. A crankarm designed for use with thisspindle will have the middle of thecrankset 47.5mm from the bikecenter line.

Manufacturers often specify both

spindle length and chainline, asboth concepts are related. Forexample, cartridge bottom bracketsmay come in various spindlelengths. For example, the 118mm is5mm longer than the 113mmbottom bracket. The chainline ofthe 118mm of this particular model50mm. The 113 has a chainline of47.5mm, or 2.5mm smaller. This isbecause in this case the 5mmshorter spindle is split betweenevenly between the left and rightsides. However, a different modelof spindle is available in 109.5mmor 118.5mm lengths. The differencein spindle length is 9mm. The

chainline of the 109.5mm is 43.5,and the chainline of the 118.5 is45mm. The difference between thespindles in not even split betweenthe two different lengths.

Often, the combination of crankarmand spindle determine chainline.This is especially the case for thesquare-type spindles because theexact fit inside the square fitting ofcrankarms varies between brandsand even between arms of thesame model. It is sometimesnecessary to simply guess at abottom bracket for a bike, installthe crank and then measure theresults. The results will then let you

know if a longer or shorter chainlinespindle should be installed.

It is often useful to know theexisting position of the front ringsrelative to the bike center plane.However, it is difficult to take adirect measurement from the centerof the bike to the center of the frontrings. It is necessary to take severalmeasurements, and then determinechainline by adding or subractingthe measurements.

The accuracy of measuring forchainline is limited by the accuracyof the frame. If the bottom bracketor frame tubing is not centered, thechainline measurements may be

off. In our example here, we willassume the frame is aligned andshell is centered. Begin bymeasuring the diameter of thedowntube, and divide this numberby 2. In our case, the seat tube is44mm, so it is 22mm from the rightside edge the tube the bike centerline.

Next, measure the distance fromthe downtube edge to the middle ofthe chainrings. On a two-chainringbike, begin by measuring from thelargest ring to the tube. Our bikebelow measure 29mm from theouter ring to the tube. Next,measure the outside-to-outise of

the two chainrings, and divide thisby 2. The bike below is 9.8mmoutside-to-outside, making it4.9mm to the middle. Deduct4.9mm from the 29mm, and it is24.1mm from the middle of rings tothe tube. Add the 22mm for thetube-to-center, and it is 46.1mmfrom the middle of the cranksetrings to the centerline of the bike.

For three chainring bikes, measure

from the outer edge of the middlering to the tube. Next, measure thethickness of the ring at the tooth. Inour example, it is 23mm from themiddle ring to the tube. Next,measure the thickness of the ring atthe teeth. In the example below, atooth is 2mm wide. Divide the 2mmby 2 to reference the middle of themiddle ring. Deduct this 1mm fromthe 23mm, making it 22mm fromthe crankset center to the tube. Addthis to the 22mm of tube to bikecenter, and it is 44mm from themiddle of the rings to the centerlineof the bike.

Chainline from Rear HubIt is possible to estimate thedesired chainline of a bike from therear cogs. This method assumes theframe is aligned, or that youaccount for misalignment in thecalculations. See Frame Alignment.

Procedure for determiningchainline:

1. Measure from the outer mostcog face to the face of thelocknut. This can be done withthe wheel in place, or with thewheel removed. If measuring inplace, use feeler gauges oreven hex wrenches to measure

the distance from the innerface of the right dropout to theface of the smallest cog. Thesetwo options are seen in theimages below.

2. Measure the width of the rearcassette or freewheel cogsfrom outside to outside cogfaces. Below is a chart of thecommon cassette systems.

3. Measure the hub width fromlocknut to locknut face. It ismost accurate to remove wheeland cogs.

4. To determine the rear cogschainline, use the formula:

(Hub width÷2) - (Cassettewidth÷2)- Gap to frame =Chainline of Rear Cogs

What is desired in the formula isthe distance from the bike"™scenter plane to the cogset middle.Taking the hub width and dividingby two defines the mid plane orcenter of the bike. Dividing thecogset width defines the middle of

the gears. The gap from the cogsetto the frame is then deducted. Theresulting number represents thedistance from the bike center planeto the middle of the cogset, orchainline.

To help speed the process, findbelow some typical cogsetmeasurements. It is always best tomeasure your own set, as thesenumbers may not represent yourcogs exactly.

Campagnolo® cassette 10speed: 38.8mm

Shimano® cassette 10 speed:37.2mm

Campagnolo® cassette 9 speed:38.2mm

Shimano® cassette 9 speed:36.3mm

SRAM® cassette 9 spped:36.5mm

Campagnolo®: cassette 8speed: 36.9mm

Shimano® cassette 8 speed:35.4mm

SRAM® cassette 8 speed:35.4mm

Shimano® cassette 7 speed:31.9mm

SRAM® freewheel (thread ontype) 8 speed: 36.8mm

SRAM® freewheel (thread ontype) 7 speed: 31.8

As an example, assume some hubis 130.6mm wide at the locknuts.The bike is a Shimano® 8 speed.The cogs are about 35.4mm wide.Assume we measure the outer cogto frame and find it is 4.5mm.

The bike center line is in the middleof the hub, so the center line is a65.3mm from each locknut. Thecogset middle is then:

(130.6÷2) - (35.4÷2) - 4.5 =43.1mm

The rear cog middle is effectively43.1mm from the bike center line.The front chain rings should beabout the same distance from thecenter line. It is possible, however,to still have acceptable shifting withless than perfect chainline.Manufacturers typically specify a

front crankset chain of slightlylonger than the rear chainline. Inthis case, as 45mm chainline wouldlikely work. A 50mm chainlinewould probably be too long.

Shifting Issues Relatedto ChainlineIf either the front or rear sprocketsare either too much inward oroutward relative to the other, theremay be certain shifting problems.However, if a bike chainlinemeasures off, yet the bike has noproblems shifting, the bike shouldbe considered acceptable. No"fixing" of the chainline is then

required. The following are typicalproblems that may be caused bychainline issues.

Chain jumping off large chainringwhen front derailleur is correctlyadjusted.

Chain riding off lower derailleurpulley when derailleur or hangeris not bent

Chain rattling on inner faces offront chainrings.

Chain derailling off innerchainring when front derailleurcorrectly adjusted.

Front derailleur cannot be

adjusted to stop over shiftswhile still allowing good shifting.

On certain bikes, the chain maytend rub and rattle against the frontrings while riding in certain gearcombinations. This is common onmany bike when riding in the so-called "cross-chaining" combinationof the smallest front ring, and thesmallest rear cog. An example of agear combination that is likely torub is shown below.

Generally, the shorter distance fromthe bottom bracket to the rear hub,the more likely a rattle from gearcombinations will occur. There mayin fact be several gears that areunuseable on any given bike. It ispossible to minimize or eliminatethis problem by moving either thefront or rear cogs. Even if the bikeis has so-called perfect chainline, itmay help the riding and shifting tocreate an "error" to solve shiftingexisting issues.

Bar End Shifter ServiceThis article will discuss bar endshifters. These are derailleur shiftlevers mounted to the ends of timetrial or triathlon handlebars (Figure1). They are also found on dropstyle handlebars (Figure 2).

Figure 1

Bar end shifters on a time trialhandlebar.

Figure 2Bar end shifters on drop style bars.

The bar end shifters mountinternally to the handlebar using an

expansion plug. Handlebarstypically must have an insidediameter of approximately 19-21mm. The shifter body and boltare made with a cone shaped endthat push into a set of wedges(Figure 3). The wedges thenexpand and tighten insidehandlebar.

Figure 3The component parts of the bar endshifter.

To access the mounting bolt, it isnecessary to remove the shift lever.Insert a 6mm hex wrench throughthe lever body and into the back ofthe mount bolt. The hex wrench fits

into the back of the mounting bolt.Turning bolt clockwise as viewedfrom end of lever frees bolt fromthe internal wedges (Figure 4).

Figure 4Securing the lever body.

To secure body, turn hex wrenchcounter-clockwise. This turn bolt totighten it into the wedges inside ofhandlebar. When working with barend levers, always remember thebody acts as the nut. The head ofthe bolt is inside the lever, and thehex wrench is fitting into the end ofthis bolt (Figure 5).

Figure 5Hex wrench turn cone-shapedmounting bolt.

After securing shift lever body tohandlebar, assemble shift leverparts to body and secure leverscrew with screwdriver (Figure 6).

Figure 6Secure shift lever parts to leverbody.

Install gear wire through lever andinto housing. Housing must fullyseat into lever body. Securehousing to handlebars with tape.

This can later be covered withhandlebar tape as desired (Figure7).

Figure 7Bar end shifter mounted to forward-

facing aero bar extensions.

Handlebar tape may then bewrapped over the housing (Figure8).

Figure 8Bar end shifter housing under

handlebar tape on a drophandlebar.

Shift wire may be removed or installwith the lever mounted in the bar.Loose wire pinch bolt and free wire.Pull wire from lever (Figure 9).

Figure 9Remove or install derailleur wire

from bar end shifter as necessary.

Shift Housing LengthTypical Tools andSupplies Cable Cutter:CN-10

Brake housing and cables asneeded

Shift housing (compressionless)and cables as needed

Housing end caps (ferrules) asneeded

Light lubricant

Mill file (for brake housing asneeded). Bench grinder ordermel also useable.

Hex wrenches for cable binderbolts

This article will discuss the cuttingand sizing of both brake andderailleur housing. See also relatedarticles on brake and shift levers.

The Park Tool CN-10 Cable Cutter isdesigned to cut multi-strand wiressuch as gear and brake cable, brakehousing, and compressionless gearhousing. Compressionless shifthousing uses many inner supportwires running longitudinally withthe inner plastic liner.Compressionless shift housing isintended for shifting systems only,not braking. Brake housing is

commonly made of a wire woundaround a plastic liner. Use endscaps or ferules at the ends ofhousing when ever possible. Thereis also available a woven orbraided-type of housing that is maybe used for both brake housing andshift housing. It is recommended tolubricate inside the housing or thecable is installed.

The jaws of the cable cuttersurround and then shear thematerial. Using plain diagonalcutters can simply flatten andsmash cables. As with all cuttingtools, it is recommended to weareye protection.

Grab and hold the cable or housingclose to the jaws. Use care not tocut your fingers. Hold cable orhousing perpendicular to jaws andsqueeze levers quickly for a cleancut, as seen below.

After cutting the compressionless

gear housing, inspect the end tosee if it flattened a bit. Use thecrimper section of the CN-10 toopen up the housing and inner linerbefore installing an end cap andcable. You can also use the crimpersection cutter to crimp on a cableend cap, as seen below.

How Long Should

Housing Be?Brake and gear housing allows thecable wire to be routed aroundbends and connects the levers tothe frame stops. The less the dragon the cables, the better for theshifting and braking. Too short ofhousing will cause it to kink andbind, making even more friction. Asa rule of thumb, try to size thehousing so it is as short as possiblebut it still enters the stops andbarrel adjusters in a straightapproach. For the rear derailleurhousing, note especially how thehousing enters the barrel adjuster.

In the left image above, thehousing bends immediately uponleaving the barrel adjuster. This canactually bend the housing end cap.The image to the right shows howlonger housing in this case allowsthe housing to enter straight.

The left image above is a typicalnew bike housing length. Thehousing bends and kinks as itenters the barrel adjuster. Theimage to the right shows longerhousing allowing a straight entryinto the barrel adjuster.

The image above shows brake andshift housing which is much toolong. The housing could beshortened and still have a smooth,straight approach to the levers andhousing stops.

The routing of housing may affectthe length. Typically the frontderailleur shift housing is run on theleft side of the frame, while the rearderailleur shift housing is run on theright. This may at time causeunnecessary bending in thehousing. In some cases, it ispossible to "cross over" thehousing, running the front shifter tothe right side stop, and the rearshifter to the left side stop. It willthen be necessary to again crossthe cable. Consider this option, butif the cable ends up rubbing theframe, it is not a good idea. Theremay be some light rubbing between

cables, but this would result in lessfriction than poorly routed housing.

Shift lever housing that is too long.Housing passes center line of bike,then must bend back to housingstops.

Shift housing is crossed over atheadtube, and crossed again ondowntube. Arc of housing is muchsmoother than black housing inexample of too long housing.

Cutting Brake HousingBrake housing is typically made of

single strand flat wire wrappedaround an inner plastic tube. Thishousing may be cut with the CN-10,or diagonal cutting pliers. Becauseof the design of the housing wire, itis not always possible to get a flat,clean cut. It is best to finish anyburr with a file. Lightly grinding theend will also improve the housingand reduce friction.NOTE:Compressionless housing does notrequire finishing.

Bottom Brackets

Cartridge Bearing TypeBottom Bracket Service(BBT)Typical Tools and Supplies Needed.

Park Tool Bottom Braket Tool:BBT-22 (or the previous versionBBT-2) -a splined driver to fitthe bottom bracket rings), orBBT-18 for eight notchTruvativ® and Bontrager®.For square type Campagnolospindle cartridge bottombrackets, BBT-4.

Park Tool torque wrench TW-2,or TW-6. Optional, but

recommended.

A 32mm headset wrench, or alarge adjustable wrench, if youdo not have a torque wrench.

Medium grade thread lockingcompound, such as Loctite #242

Grease, such as Park Tool PPL-1Polylube 1000 or ASC-1 AntiSeize compound

This article will discuss the removaland installation of the commoncartridge bottom brackets of thethree-piece cranksets.

Most cartridge bottom brackets areheld by retaining rings or cups on

either side. The description below isbased on the Shimano® brand ofbottom bracket, but most othercartridge type bottom bracketbearing units install in a similarfashion. NOTE: Shimano® XTRBB950 bottom bracket and Dura-Ace BB-7700 bottom brackets areadjustable type bottom brackets.See Adjustable type BottomBrackets

For the External Bearing SystemCranksets, such as Shimano®Hollow Tech II, or Campagnolo®Ulta-Torque bottom bracket-crankset systems, see ExternalBearing System Service.

There are two different styles ofShimano® cartridge bottombrackets. One type has a fixedflange on the right side (drive side).The other type has a fixed flangeon the left side (non-drive side).Each one uses a removable ringopposite the fixed flange. See thefigure below.

There is a fairly simple test todetermine if the bottom bracketbearing is worn out. Shift the chainto the inner most rear sprocketsfront and rear. Drop the chain offthe smallest front ring, and arrangeit so it will not strike the chainrings.

Spin the crank while holding thebike with one hand. If you feel anobvious rumbling or grindingfeeling, the bearing are wore outand the unit should be replaced.Very worn bottom brackets willactually make a grinding noise.

Removal of Cartridge

Bottom BracketBegin bearing service by firstremoving both cranks. For squaretaperred spindle types, seeCrankarm Removal. For roundsplined type spindles and arms seeSplined Arm Removal.

Some bottom bracket models use asteel or aluminum ring on one sideand a plastic ring opposite. Onthese models, remove the metalside first regardless of left or rightside. Otherwise, insert BBT-22 (orBBT-2) fully into splines on left side.Some brands use an eight notchedring, which will accept the BBT-18.

Use care to hold either tool firmly inplace. Remove the non-drive sideby turning counter-clockwise. Forsome models, this removes thering, in some models this pull thecartridge body out.

Insert BBT-22 (or BBT-2) or BBT-18fully into splines on opposite side.For non-drive side, remove byturning counter-clockwise. For driveside, turn clockwise to remove.

The spline system used on many

cartridge bottom bracket is veryshallow. If the spindle is hollow, usethe rear hub skewer to hold the toolfirmly in place. When using thistechnique to remove the spindle,break the threads free, then loosenthe skewer as the cup comes out.

THREADING NOTE: Most modernbikes use an ISO thread standardfor the bottom bracket. The leftside thread is a right-hand directionthread, which tightens clockwiseand removes counter-clockwise.This standard is also called Englishor BSC. The right side (drive side)thread is a left-hand thread, whichtightens counter-clockwise andremove clockwise. There are someexceptions to the ISO. Bikes madein Italy may use "Italian" threading,with both drive and non-drive sidesright hand thread. There may bemarkings such as "36 x 24" on thecups. Older bikes from France may

have right hand threads on bothsides (35mm x 1mm). It isespecially recommended for bikeswith a right-hand thread for thedrive side to use a thread locker inaddition to full torque. See more onthread preparation and threadlockers a Basic Thread Concepts.

Below is an image of the commonISO threaded cups. Note thethreads of the left-threaded (driveside) cup slope upward to the left.Threads of the right-threaded (non-drive) cup slope upward to theright.

Cup direction for non-drive (left sideof bike) and drive side (right side ofbike) are shown below for thecommon ISO/English bottombrackets.

Non-drive (left side) cup direction.

Drive side (right side) cup direction.

Seized CupsIt can occur that the cup becomesseized in the frame. Be sure todouble check thread direction whenin doubt. The common 20-tooth

internal spline cup has shallowsplines for tool engagement. Use along bolt to secure the BBT-2 to thecup. A skewer can be used if thespindle is hollow. Use a bench viseto hold the tool. The frame becomethe lever. Again, double checkthread direction before turning.Soak threads with a penetratingfluid before attempting removal.

Cup and Lockring TypeThere several variations on thecartridge bottom bracket system.One type uses cups and seperatelockrings on both side. The bearingsare typically common industrialtypes. The cups are removed and

then the bearings replaced. In theimage below, the cup looks similarto the adjustable bearing types. Alockring spanner is used on thelockring, and then a spanner suchas the SPA-4 is used in the cup. Thecup is run up to the bearings andthen the lockring is secured. Thereis no bearing adjustment in thissytem.

Installation of CartridgeBottom BracketBegin by preparing the threads ofthe bottom bracket. A thread lockermay be used when the frame shellis steel and the cups are either

aluminum or steel lockrings. A mildthread locking compound such asLoctite® #242 that is considered"service removeable" is preferred.This means that the parts areremoveable with normal tools andwithout taking extreme measures.If no thread locking compound isavailable, grease threads heavily orASC-1 Anti Seize Compound. Formore on thread preparation seeBasic Thread Concepts.

If the bottom bracket frame shell isaluminum or titanium, use ParkTool ASC-1 Anti Seize Compound.Even if lockrings are steel, use anti-seize. Anti-seize is available at

some bicycle stores, hardwarestores, or automotive parts stores.Grease can be used in place of anti-seize, but anti-seize is more durableand provides better lubricationduring tightening. Apply this only tothe threads.

Plastic lockrings or cups need onlygrease on the threads. Do not usethread lockers on plastic as thechemical may cause the plastic tobecome brittle.

It can sometimes happen a bottombracket can creak where thelockring or cups meet the bearingbody. To prevent this, apply athread locking compound such as

Loctite #242 to the inside area ofremovable ring, where it meets thebody. This will help prevent anycreaking in the future. With plasticrings, do not apply any threadlocking compound.

Look on body of cartridge for "L"and "R". "L" goes to left side ofbike, and "R" goes to right side ofbike. For most bikes, the right side("R"), has left-hand directionthreads, thread this side in turningcounter-clockwise. The left side("L") has right-hand directionthread, so thread this side inturning clockwise. (See THREADNOTE on thread direction above.)

Thread the cartridge body intobottom bracket by hand, beingcareful not to cross thread.

Use BBT-22 or BBT-18 asappropriate to snug fixed flangeagainst face of bottom bracket.

Thread in removable ring toappropriate side.

Secure removable ring to at least360 inch pounds using torquewrench. If you are using handwrench, and are holding the wrench6 inches from axle, apply 60 poundsof pressure"¦ which is tight. Bysecuring removable ring, you aresecuring the other side at the same

time. Removable ring pushesagainst fixed flange.

Install cranks. For spline typecranks, see ISIS Drive or Octalink.For other see Square Spindle TypeRemoval.

Brake Service

Linear Pull BrakeService (V-brake style)Useful Tools andSuppliesRepair Stand, holds bikesecure for easy work.

Hex wrenches(commonly 5mm and6mm)

Cable cutter, ParkTool CN-10

Grease, Park Tool

Polylube® 1000 Light liquid lubricant File, or grinder tofinish housing ends

RagsService ProceduresProperly adjusted brake systemsrequire attention to small details.This article will begin by discussingthe brake lever, inner wire fitting atthe lever, and brake housing.Caliper attachment to the frame,pad adjustment to the rim, and padcentering and clearance are then

reviewed.

Brake LeversBrake levers should be positionedso they are easy and comfortable toreach. Loosen the lever mountingbolt and rotated the lever so it is inline with the rider"™s arm, makingit comfortable to reach and use. Re-secure brake lever body.Additionally, brake levers commonlyhave a setscrew on the lever bodythat allows the lever to be setcloser to the grip. Use reach-settingscrew to adjust lever reachaccording to hand size and ridingstyle.

Cable SystemThe cable system connects thebrake lever to the caliper at thewheel. The brake inner-wire has afitting on one end, which sits in thelever. Upright bar levers use around disc shaped end about 7mm(9/32") in diameter.

The brake inner wire end is held bythe lever. The common system isshown below. Align the slot in thebarrel adjust with the slot in thelever body. Fit the disc into thelever and pivot the wire into theadjustingbarrel. Turn the barrel tohold the inner wire in place.

The Shimano® levers may use aclamp on the lever. Pull this clampupward, and fit the inner wire discin place.

The inner-wire passes through abrake housing, which allows theinner-wire to connect from thelevers to housing stops on theframe. Housing also allows for

bends around corners on the way tothe brake caliper.

To determine correct housinglength, see Housing Length.

Calipers and PadsLinear pull calipers are attached tothe frame or fork at the "braze-on".If you are mounting the calipers orhave removed them, grease thebraze-on before installing thecaliper. There may be threedifferent spring hole options, it istypically best to choose the middlehole.

Brake pads are bolted to the caliperarms. When the bolt or nut isloosened, they can be adjustable inseveral directions. The pad shouldbe correctly adjusted for verticalheight alignment, tangent

alignment, vertical facealignment and pad toe. Notevery brand or model of brakecaliper has every adjustment, andsometimes you must simplycompromise when setting pads.

Vertical height alignment: Thisis the setting up and down on therim-braking surface. View caliperface-on and move the arms,watching the pads move to the rim.For most linear pull calipers, set thepad to the upper edge of the rim-braking surface.

Some linear pull models, such asShimano® XT and XTR, use aparallelogram movement for thepad, and the pad travels straight tothe rim. Set these pads to strike inthe middle of the rim-brakingsurface.

Tangent AlignmentThis is the setting of the pad tilt.Viewed pad from the side, the frontand back of the pad should be levelto the rim. One side should not behigher or lower than the other side.Use care when tightening the padfixing bolt and hold the brake padto keep it from twisting.

Vertical face alignmentThis is the setting of the padvertical surface relative to the rimvertical surface. The vertical face ofthe pad should be set parallel tothe face of the braking surface.

Pad ToeingThis is the setting of pad angle as ittouches the rim. Toeing refers tosetting the pad so the pad"™s frontedge strikes first, which tends toreduce squeal during braking.

Caliper arms tend to have play inthe pivots and the arms flex whenthe brake is applied. This maycause squealing in the brake pads.It is simplest to first ride the bikeand see if the brakes squeal.

Front of pad strikes rim first for"toe".

Most models of linear pull calipersuse a "threaded stud brake pad."Some models use a smooth studpad with fixing bolt. For the

threaded stud types, a threadedbolt is fixed into the pad. The bolt issandwiched to the caliper arm by aseries of convex and concavewashers, creating a ball and socketsystem. The bolt and pad move inthe caliper arm for toe and verticalface alignment.

Threaded-stud pads use curved

washers to align pad face to rim.

Setting PadsBefore setting pads, begin bydouble checking that wheel isadequately centered in frame. Ifwheel is moved from currentposition, pad alignment will beeffected.

1. Loosen pad nut/bolt andlubricate curved washers andthread. Adjust one pad to therim at a time.

2. If desired, install rubber bandshim at back edge of pad. Thishelps set toe.

3. Push caliper arm to rim andview pad alignment. Align padcorrectly in four positions.

Set pad vertical height on rim

braking surface.

Set pad vertical face to beparallel to rim face

Set front and back edge of padshould be level to rim, so itis tangent to rim.

If toeing with shim, set sofront edge and back edgewith rubber band should betouching rim at same time.

4. Tighten pad nut and removerubber band. Inspect padalignment again.

5. Repeat alignment of other pad.

Attach inner-wire to brake caliper.

Secure wire fixing bolt. Squeezelever hard several times and setpad clearance at lever for riderpreference. If brake feels tight, turnbarrel adjuster into lever clockwiseto loosen inner-wire tension. Ifbrake feels too lose, turn barreladjuster counter-clockwise totighten inner-wire tension. If barreladjuster is all the way engaged atlever and brake lever still too tight,loosen inner-wire pinch bolt andallow slack to feed through pinchplate. Tighten pinch bolt and testagain, doing final adjusting at brakelever barrel adjuster.

Use barrel adjuster to set tightnessof pads to rim.

Inspect pad centering to rim. Useset screw on sides of caliper tocenter pads to rim. Tightensetscrew on arm with pad that isclosest to rim. Inspect that pads arenot rubbing tire. Re-adjust ifnecessary. Clean the rim surface

and test ride bike.

Use centering screws to move armsand center pads to rim.

Pad WearPads will wear out with use andrequire replacement. Pads will also

harden and become ineffective withage. Pads may also becomeembedded with aluminum or othercontaminants. Inspect and removeas necessary. Pads that are alignedtoo low on a rim will tend todevelop a lip on the low edge. Thislip makes correct alignmentimpossible.

Housing LengthTypical Tools andSupplies

Cable Cutter:CN-10

Brake housing and cables asneeded

Shift housing (compressionless)and cables as needed

Housing end caps (ferrules) asneeded

Light lubricant

Mill file (for brake housing asneeded). Bench grinder or

dermel also useable.

Hex wrenches for cable binderbolts

This article will discuss the cuttingand sizing of both brake andderailleur housing. See also relatedarticles on shift levers or brakelevers.

The Park Tool CN-10 Cable Cutter isdesigned to cut multi-strand wiressuch as gear and brake cable, brakehousing, and compressionless gearhousing. Compressionless shifthousing uses many inner supportwires running longitudinally withthe inner plastic liner.

Compressionless shift housing isintended for shifting systems only,not braking. Brake housing iscommonly made of a wire woundaround a plastic liner. Use endscaps or ferules at the ends ofhousing when ever possible. Thereis also available a woven orbraided-type of housing that is maybe used for both brake housing andshift housing. It is recommended tolubricate inside the housing or thecable is installed.

The jaws of the cable cuttersurround and then shear thematerial. Using plain diagonalcutters can simply flatten andsmash cables. As with all cuttingtools, it is recommended to weareye protection.

Grab and hold the cable or housingclose to the jaws. Use care not tocut your fingers. Hold cable orhousing perpendicular to jaws andsqueeze levers quickly for a cleancut, as seen below.

After cutting the compressionlessgear housing, inspect the end tosee if it flattened a bit. Use thecrimper section of the CN-10 toopen up the housing and inner linerbefore installing an end cap andcable. You can also use the crimpersection cutter to crimp on a cableend cap, as seen below.

How Long ShouldHousing Be?Brake and gear housing allows thecable wire to be routed aroundbends and connects the levers tothe frame stops. The less the dragon the cables, the better for theshifting and braking. Too short ofhousing will cause it to kink and

bind, making even more friction. Asa rule of thumb, try to size thehousing so it is as short as possiblebut it still enters the stops andbarrel adjusters in a straightapproach. For the rear derailleurhousing, note especially how thehousing enters the barrel adjuster.

In the left image above, thehousing bends immediately uponleaving the barrel adjuster. This canactually bend the housing end cap.

The image to the right shows howlonger housing in this case allowsthe housing to enter straight.

The left image above is a typicalnew bike housing length. Thehousing bends and kinks as itenters the barrel adjuster. Theimage to the right shows longerhousing allowing a straight entryinto the barrel adjuster.

The image above shows brake andshift housing which is much toolong. The housing could beshortened and still have a smooth,straight approach to the levers andhousing stops.

The routing of housing may affectthe length. Typically the frontderailleur shift housing is run on theleft side of the frame, while the rearderailleur shift housing is run on theright. This may at time causeunnecessary bending in thehousing. In some cases, it ispossible to "cross over" thehousing, running the front shifter tothe right side stop, and the rearshifter to the left side stop. It willthen be necessary to again crossthe cable. Consider this option, butif the cable ends up rubbing theframe, it is not a good idea. Theremay be some light rubbing between

cables, but this would result in lessfriction than poorly routed housing.

Shift lever housing that is too long.Housing passes center line of bike,then must bend back to housingstops.

Shift housing is crossed over atheadtube, and crossed again ondowntube. Arc of housing is muchsmoother than black housing inexample of too long housing.

Cutting Brake HousingBrake housing is typically made of

single strand flat wire wrappedaround an inner plastic tube. Thishousing may be cut with the CN-10,or diagonal cutting pliers. Becauseof the design of the housing wire, itis not always possible to get a flat,clean cut. It is best to finish anyburr with a file. Lightly grinding theend will also improve the housingand reduce friction.NOTE:Compressionless housing does notrequire finishing.

Brake LeversUseful Tools andSuppliesThis article will discuss the cable(inner wire) installation in brakes.MTB levers secure to the handle barby a clamp bolt. It is generallyacceptable to secure the bolt so thelever body will move when forced.This may help prevent damageduring a crash. Because therider"™s body weight held by thehandlebar, not by the brake leverbody, it is possible to not have thebody fully secure. Generally, beginalignment so the lever body is in

line with the rider"™s arm.

MTB-type Brake Lever CableAttachment

MTB-type brake lever.

The MTB-type brake cable uses adisc shaped end. The lever willhave a fitting in lever for this disc.Typically, begin by lining up a slotin the adjusting barrels.

SRAM® levers feed from the insidethrough the lever body.

For Shimano® type levers, engagecable end in lever first, the fit intoadjusting barrel.

The dropbar type lever body oftenis used by the rider to support

his/her weight. This effectivelymakes the lever similar to a "bar-end" extension. Secure these leversfully. The body should not move,even with the full weight of the userpushing downward.

Shimano® aero-type levers bodybolt is on the under rubber hood ofthe outside of each lever.

Campagnolo® aero-type levermounting bolts are under the upperoutside corner of each rubber hood.

CABLE ATTACHMENTThe brake cable end attaches to thelever by fitting through a socketcalled the brake cable anchor pivot.

Feed the cut end of the wirethrough the hole in the pivot andout the backside. If the handlebarsare taped, it is necessary thehousing end be aligned with thecable hole in the lever body. It issometimes necessary to wiggle theend until you find the housing end.

Campagnolo® brake lever cableinstallation.

Move brake lever inward as you pullback to expose cable anchor pivotof Shimano® brake/shift levers.

Shimano 7900 Levers

The brake cable installs through thefront of the levers. Remove the

nameplate screw and nameplate.The plate pulls away forward. Usecare not to scar the exterior of theplate.

Remove nameplate screw

Pull nameplate forward from top

There is a reach adjustment screwbehind the nameplate, adjacent tothe cable hole. This screw turns astud that will rotate the lever downand closer to the bars.

Location of reach adjustment screw

The lever position range from fullyopen to fully tightened positionscrew

The cable access hole is the innerhole at the lever. As seen from the

front, it is the left most hole forfront shift lever, and the right mosthole of the rear shift lever .

Rear shift lever with brake cable fedthrough lever and body

Cassette andFreewheel Service

Cassette and FreewheelRemovalThis article will review the removaland installation of rear cogs onderailleur type bicycle, and of singlespeed freewheeling BMX/Freestylebikes.

Typical Tools and Supplies Needed:

Cassette cog remover FR series

Sprocket Tool (chain whip) SR-1,SR-2, or HCW-16

Freewheel tool wrench, FRW-1,(substitute large adjustablewrench or vise)

Grease, such as PPL-1 or anti-seize type lubricant

The rear cogs are attached to thehub in one of two ways. Newerbikes tend to use type hub called a"cassette hub." The cassette hubuses a "freehub" sytem, which is atype of clutch mounted to the bodyof the hub. This cylindricalmechanism ratchets counter-clockwise for coasting, and locksclockwise for driving the bike whenpedaled. The freehub body has aseries of splines on the outer shell."Cassette" sprockets slide overthese splines. A lockring threadsinto the freehub and holds the

sprockets, or cogs, in place. Whenthe cogs are removed, theratcheting freehub remains on thehub body. Most modern bicycles usethe freehub system. See a typicalcassette hub below.

Older bikes may have a large

external thread machined into thehub. The cogs and ratcheting bodyassembly, called a "freewheel,"threads onto the hub. Theratcheting mechanism comes offwith the cogs when the freewheelunthreads for removed.

To remove rear cogs, begin bydetermining the style of hub, thestyle or brand of cogs, and theremoval tool required. The removaltool must fit the part correctly, orboth may become damaged. Afterremoving the wheel, look at the flatsurfaces adjacent to the right rearaxle for brand names.

You will need to determine thestyle of hub you have and the styleor brand of cog system. The tablebelow shows several differentoptions.

FR-1 Shimano® freewheel 12splines, approx. 23mm diameter

FR-2 Older Suntour® two notched,25mm across

FR-3 Suntour® four notched,24mm across-

FR-4 Atom® and Reginia® 20splines, approx dia. 21.6mm

FR-5, or FR-5G with guide pin 12splines, approx. 23.4mm diameter

FR-6 BMX and Freestyle one-speed4-notch freewheels-4 notches,40mm across

FR-7 Falcon® brand freewheels-12splines, approx 23mm diameter

BBT-5/FR-11 Campagnolo

cassettes-(for Campagnolocassettes, not freewheels) 12splines, approx. 22.8mm diameter

FR-8 Compact single speed(30mmthread, "flip-flop hubs")

There may be older modelfreewheels where a tool is no toolavailable. It may still be possiblere-use the wheel but at the loss ofthe freewheel. There are alsocurrent models of freewheels thatdo not have an adequate design forremoval. If the image below, thefreewheel has two very narrow andshallow notches that do not allow

enough purchase for a tool.Removal of this type of freewheelwould likely result in ruining thetool, the freewheel, or both. Foreither situation, see destructiveremoval of freewheels

Very narrow and shallow removalnotches in a single speed.

This model of freewheel has noremoval tool fittings of any type.

Cassette Cog LockringRemoval andInstallationShimano®, Campagnolo®,

SunTour®, Sun Race®, ChrisKing®, DT-Hugi®, and otherbrands.

If your cogs look like this, youprobably have a lockring typecassette.

With the modern cassette cogsystems, all cogs are fitted withsplines. Cogs slide onto the freehubbody and are held in place by alockring. The lockring sits outwardfrom the smallest cog. Look for the

word, "LOCK", and an arrow on thelockring indicating direction to turnfor locking. Turn the lockringcounter-clockwise, the opposite wayof the arrow, to loosen it. Theremay be a loud noise when thelockring breaks loose. There is oftenknurling under the lockring to helpkeep it in place, and this knurlingmakes noise when the ring isloosened or tightened.TOOLS: Park Tool FR-5, (ForCampagnolo use BBT-5/FR-11),Park Tool SR-1 sprocket chain whip(2 if possible), or large adjustablewrench or vise.

Mount bike in repair stand and

remove rear wheel from bike.

a. Remove quick release skewer.

b. Inspect cassette and selectcorrect type of remover.

c. Engage remover intosplines/notches.

d. Install quick release skewer andinstall skewer nut on outside ofremover.

e. Snug skewer nut againstremover. Skewer acts as aholding device for freewheelremoval tool.

f. Hold cogs in clockwise directionwith sprocket chain whip tool.

Turn remover counter-clockwise, using a largeadjustable wrench, the hex endof another Park Tool sprocketchain whip tool SR-1, or thePark Tool freewheel wrenchFRW-1. It will require force toremove the lockring. Expect tohear a loud clicking sound asthe locking teeth of the lockringseparate.

g. If using a vise, grab removaltool tightly in vise with wheelheld flat. Use sprocket chainwhip tool to turn sprocketscounter-clockwise. Do not holdwheel while turning sprockets,allow wheel to rotate, and pullonly on sprocket chain whip

tool.

The process is of a typical cassettelockring and cassette stack removalis in the short clip below.

Using FR-5G with GuidePinRemove the skewer and install theFR-5G. Make sure the teeth are fullyengaged in the lockring. Hold cogsas described above and turn FR-5Gcounter-clockwise.

Installing Cassette CogsCassette freehub bodies andcassettes are often designed so thecogs will fit in only one orientation.This permits manufacturer to align"shifting ramps" to specification.

a. Inspect splines of freehub body.Look for a wide space betweensplines. Inspect the internalsplines of cogs. Look for a widespline to mate with wide space infreehub body. Align splines andengage all cogs.

b. Install spacers in sameorientation as when removed.

c. Grease threads of lockring andthread lockring into freehub.

d. Install cassette lockring tooland install quick release skewer.Thread skewer nut on outside oflockring tool.

e. Snug skewer nut against

remover. Skewer acts as a holdingdevice for freewheel tool.

f. Turn remover clockwise untillockring is tight, at least 360 inch-pounds (approximately 40 Nm).For installing lockring, use of thesprocket chain whip tool is notrequired.

FR-5G speeds installation as well.Simply insert the FR-5G into thelockring splines and tighten fully.

Threaded FreewheelRemoval andInstallation

This type of freewheel requires theFR-1

These types of cog systems willhave either recessed notches orsplines that sit inside and lowerthan the smallest cog. OlderSuntour freewheels had tworecessed notches. Some Suntourfreewheels come with four recessednotches. Shimano freewheels and

Sachs freewheels have a series ofsmall square shaped splines. Atomand Regina freewheel use a seriesof star shaped splines. Park Toolmakes freewheel removes for allthese types of freewheels. NOTE:Falcon freewheels have a largerspline than Shimano. Use only theFR-7. DO NOT use the FR-1 on theFalcon freewheels.

a. Mount bike in repair stand andremove rear wheel from bike.

b. Remove quick release skewer.

c. Inspect freewheel center andselect correct type of remover.

d. Engage remover into

splines/notches.

e. Re-install quick release skewerwith skewer nut on outside ofremover. If solid axle-type, useaxle nut to hold frewheel tool.

f. Snug skewer nut againstremover. Skewer acts as a holdingdevice for remover.

g. Turn remover counter-clockwiseusing a large adjustable wrench.Park Tool removers will also fit thehex end of the Park Tool sprocketchain whip tool SR-1, or the ParkTool freewheel wrench FRW-1. Itwill typically require some force toturn the freewheel. Another option

is to mount remover flats in hardjaws of vise, and turn rim counter-clockwise.

h. Turn remover only 1 fullrevolution counter-clockwise.Loosen and remove skewer beforecontinuing to remove freewheel.

i. Continue to turn removercounter-clockwise until freewheelis unthreaded from hub. Liftfreewheel from hub.

Installing Freewheela. Lubricate heavily with grease oranti-seize inside mounting threadsof freewheel.

b. Lay wheel on bench, and holdflat. Hold freewheel so cogs areparallel to wheel rim and lowerfreewheel onto threads.

c. Sight right side of hub andfreewheel. Axle should appearcentered in hole of freewheel. Ifaxle appears off center, freewheelmay be cross-threaded on hubthreads. Remove and re-align.

d. Begin threading cogs clockwiseby hand until freewheel feels fullythreaded. If a great deal ofresistance is encountered, removeand attempt better threadalignment.

e. Use sprocket chain whip tool torotate cogs clockwise. This willfully seat freewheel against hub.

f. If a new freewheel was installedor in new wheel installed, checkall adjustments of the rearderailleur. See Rear DerailleurAdjustments.

There are some brands and modelsof thread-on freewheels that haveuse a lockring to hold the cogs tothe freewheel body. This lockringcan sometimes be removed,however, there is typically no needto do so. Individual cogs of thesefreewheels are not typicallyavailable. The lockring is used to

assemble the freewheel unit, and itis not intended for service. Whenthe cogs wear out, the entirefreewheel as a unit must bereplaced. In the freewheels below,notice the cog lockrings. The topfreewheel uses the FR-2, a doubleprong freewheel tool. The bottomfreewheel uses the FR-1, a splinedtool.

Older Cassette Hubs(non-lockring ring typefreehubs)

a.Older freehubs may lack notchesor splines adjacent to axle. Theseolder freehub cogs did not use afreewheel or cassette lockringremoval tool. There will be a dustcap for the hub on the right side,

but no recessed notches or lockringsplines at all. The first cog acts as alockring for the other cogs.

b.Use two sprocket chain whip tool(Park Tool SR-1 or SR-2)

c.Place first sprocket on second orthird cog, holding it clockwise.

d.Place second sprocket tool on firstcog to rotate it counter-clockwise.

e.Arrange sprocket tools so theyform a "X". This gives you bettermechanical advantage. See imageabove.

f.Rotate first cog counter-clockwisewhile holding second sprocket chainwhip tool. This loosens first cog.

Remove cog and pull off other cogs.

Installing Older Non-Lockring Freehub Cogsa. Grease threads of smallest cog.

b. Install cogs and spacers onfreehub.

c. Thread on smallest cog andsecure clockwise with sprocketchain whip tool.

Crank Service

Crank Installation andRemoval- SquareSpindle TypeThis article will discuss the removaland installation of cranks fromsquare spindle bottom brackets.Crank pullers are used for two basiccrank types: the square spindletype arms, and the splined typespindle arms. Figure 1 below is acrank with the bolt removed. Thesquare spindle can be seen insidethe square fitting in the arm. Figure2 shows a bottom bracket bearingunit with square spindle.

Figure 1. Crank without boltshowing square hole and squarespindle end

Figure 2. Common square spindle ina bottom bracket bearing assembly

For the splined Shimano® Octalinkand ISIS Drive® type cranks seeSpline Cranks.

Typical Tools andSupplies Required:

Crankbolt wrench: typically 8mmhex wrench for newer bikes,such as HR-8

14mm or 15mm socket anddriver (older bikes), or Park ToolCCW-5 for 14mm size bolt heador 8mm hex cap screw

Crank puller- Park Tool CCP-22or CWP-7

Adjustable wrench

Rags

Grease such as PPL-1

Torque wrench, if available, suchas TW-2 or TW-6, and correctsocket bits, such as the SBS-1

for crank bolt/nut

Cranks connect the pedals to thebottom bracket spindle. The armsare pressed tightly to the bottombracket spindle. Cranks must beremoved from the spindle to servicethe bottom bracket bearings. Onsome models of cranks, the cranksmust be removed to replace thechainrings.

One-Key Release ("selfextracting")

Some cranks are sold with a "one-key release" or "self extracting"system (Figure 3). No crankremover is required. Leave the

retaining ring ("dust cap") in placeand turn the crank bolt counter-clockwise.

For more detail, see Self-ExtractingCrank Systems.

Figure 3. One-key system with pinholes in retaining cap

Crank Removal (SquareSpindle Type)a. Shift chain to largest chainring toprotect hands against chainringteeth.

b. Look for bolt or nut at end ofcrank in line with bottom bracketspindle. If no bolt is visible, removedust caps (Figure 4). Some caps pryout and some thread out. NOTE: Ifthe bike has a one-key releasesystem, leave this cap in place. Aretaining ring surrounds the bolt.Simply turn the center bolt counter-clockwise to remove arm of one-keyrelease system.

Figure 4. Dust cap hiding boltbeneath

c. Inspect for bolt or nut (Figure 5,6 and 7). Turn counter-clockwise toremove. Inspect inside arms forwashers. Remove washers ifpresent.

Figure 5. Hex head bolt

Figure 6. Socket head bolt

Figure 7. Crank nut on threadedspindle stud

d. Before installing crank puller intocrank, turn puller nut away frominternal driver as much as possible.If puller nut happens to unthreadfrom internal driver, thread it backon only 3-4 turns.

e. Thread large external thread ofpuller (nut) into arm, taking carenot to cross thread. Tighten pullernut into crank using wrench (Figure8). If puller nut will not thread intoarm, or if threads in arm arestripped, see Removal of Crankswith Damaged Threads.

Figure 8. Secure puller nut intocrank

f. Thread internal driver into pullernut. Using handle or adjustablewrench, tighten driver until crank isloose on spindle (Figure 9). Pull armfrom spindle and unthread bothparts of tool from arm. Use care notto skin knuckles when removingtool.

Figure 9. Turn handle to pull armfrom spindle

g. Repeat process on other crank.

Crank Installation(SquareSpindle Type)

The video below provides a visualoverview of the installation process:

See Park Tool Video (InternetRequired)

Cranks are pressed tight onto thetapered square spindle. The squarespidle is made with a slight upwardsloping taper. The crank squarefitting also has a slight taper

(Figure 10). The crank bolt or nutacts as the pressing tool and forcesthe arm up the slope of the spindle.The bolt or nut must be tightenough to keep from loosening, butnot so tight that the spindle splitesand damages crank. If possible, usea torque wrench. See TorqueRecommendations.

Figure 10. The square hole andsquare spindle end

Aluminum cranks typically do notrequire lubrication of this press fit.Aluminum by its nature is self-lubricating as it is covered with athin layer of oxidation. Adequate

torque is typically enough to keeparms from creaking.

a. Wipe both sides of spindle andinside crank mounting holes with arag.

b. Grease under head and threadsof both bolts or nuts.

c. Install right crank onto right sideof spindle.

d. Thread crank bolt/nut to spindle.

e. Tighten crank bolt/nut tomanufacturer"™s recommendedtorques (Figure 11).

Figure 11. Fully tighen crank bolt ornut

f. Grease threads of dust cap (ifany) and install snug.

g. Install left crank onto left side ofspindle with arm pointing oppositedirection of right side arm.

h. Install crank bolt/nut and tighten.

i. Grease threads of dust cap (if

any) and install snug.

Removal of Cranks withDamaged Threads(square type only)If the removal threads for the crankpuller in the crank are damaged,there is a possible repair. Begin byinspecting the threads. If only theouter threads are bad, you may stillbe able to remove it using a normaltool. Make sure the threads of theremover are clean. Start the toolstraight to the threads and carefullythread it in place. Tighten the toolinto the crank threads with awrench before attempting to pullthe arm. Even if there are only a

few threads left, it is worth trying toremove the arm with a crankremover.

Another repair option involves atool from the Bicycle ResearchCompany, the TC-8. This is basicallya fluted bolt that cleans thethreads. It comes with a pivotingstud to align the tool centered tothe threads. This tool is not a tap, itonly aligns damaged and cross-threaded threads. It will not cutnew threads. Typically, it will notdamage threads, so there is nothingto lose in trying it. The TC-8 willwork only with square drive crankswith an 8mm threaded bolt.

If the threads are completelystripped, the arm is basicallyruined. A simple removal methoduses the concept of how arms arekept on the bike. Pressure from thecrank bolt keeps it on, so you willneed to remove that pressure.Loosen the bolt or nut three or fourturns. Ride the bike hard, uphill.The crank hole is a tapered fit ontoa tapered spindle. The flexing under

stress will cause the arm to loosen,but it will also cause the crank holeto become enlarged, ruining thearm. Use care when riding; youDon'tt want the arm to fallcompletely off when pedaling.

It is also possible to use a hacksawto cut into the arm at the spindlejoint. A cold chisel can then be usedto split the arm. Again, the arm isbasically ruined when the threadsare completely stripped, sodestructive removal should beconsidered as an option.

Trouble Shooting aCreaky or Noisy DriveTrainThis article will discuss troubleshooting noisy drive trains.

Creaking and squeaking noises areannoying, and can be a sign ofmore serious problems. Damage tocomponent parts may result if theyare left unattended. Creaking isusually caused by two thingsrubbing together, such as acrankarm rubbing on a spindle.Many of the solutions below rely onadequate torque on the parts. Seealso an article on Bicycle Torque

Specifications. Thread preparationis also critical, see also BasicFastener Concepts.

Correctly diagnosing the source ofthe noise can be difficult. It mayhelp to have a friend assist you.Have them flex the parts while youlisten and feel for noise. Creakingwill often resonate enough to befelt as well as heard.

If during a ride you hear a creak orsqueak once per revolution, it isprobably located in the cranksetand pedal area. If the noise is onceevery 2 - 3 revolutions, it may be inthe chain. There can be severalcauses of creaking. You may need

to proceed through the drive trainstep by step, part by part toeliminate potential problems. Hereare some of the possible sourcesand remedies for drive traincreaking.

CranksThe most common cause ofcreaking is the crank being loose onthe spindle. Remove the crankbolts, lubricate the threads andunder the bolt head, and re-install.Tighten the bolts to themanufacturer recommended torque.Use a torque wrench if possible.Typically, 300 inch-pound is

considered a minimum torque,which is 50 pounds of effort holdinga wrench six inches from the bolt.

ChainringsThe chainrings are held to thecranks by chainring bolts. Use a hexkey wrench and check each bolt.Hold the back chainring nut fromspinning with a chainring nutwrench, such as the Park Tool CNW-2. Again a mild thread locker orgrease on the threads is a goodidea. Secure steel chainring bolts toabout 60 inch-pounds, which isabout fifteen pounds of effortholding a wrench four inches from

the bolt.

Pedal Shoe CleatsIf you have riding shoes, the cleatsunder the shoe can loosen and alsocause noise. Use a mild grade ofthread locking compound or greaseon the bolts, and tighten them fully.Even regular "street shoes" on aplatform pedal can cause noise. Ashoe lace can tap against a

crankarm, and the rubber can moveand squeak under the sole.

PedalsTighten pedals into crankarms. The

torque typically recommended is300 inch-pounds, which is about 50pounds of effort hold a wrench sixinches from the pedal. Pedalbearings can also creak. Spin thepedal and listen for noise. Differentmakes of pedals have differentbearing service options. For moredetail see Pedal Installation

Chainring Cassette toCrankarmSome cranksets use a chainringmounting arms (spider) that is

removable from the crank arm.There is a lockring on the backsideof the arm that may needtightening. Remove the crankarmand then remove the snap ring witha screwdriver. Install the BBT-18lockring tool on the ring, and loosencounter-clockwise. Drip some mildthread locker onto the threads, thentighten the ring to 400 inch-pounds.For more details see ChainringCassette Installation

Bottom BracketThe bottom bracket may not beproperly secured into the frame.Most bike frames use a threaded

bottom bracket shell. If the bearingcups or retaining lockring are nottight, there may be movementbetween the internal and externalthreads.

ChainListen for dry links by spinning thechain in a repair stand. Lubricate asnecessary, with a drop of lubricanton each roller and rivet. Look ateach and every rivet to checkmisalignmet in the chain plates.Inspect for twists in side plate, orburrs, cuts or other damage to theside plates. Place chain in a gearcombination that relaxes the rear

cage, and spin chain backwards. Ifthe chain hops as it passes of thepulley wheels, it may have a tightlink

Derailleur Pulley (idler)WheelsThe two pulley wheels of the rearderailleur spin as the chain turns.

Use a light lubricant to quiet them.

Wheel and SpokesCreaking can be the result of loosespokes in the rim. Spoke may bemoving in the rim or spokes mayrub one another at the spokeinterlace. In either case, increasespoke tension, using a spoketension meter if possible. For moredetail see Wheel Truing. Some rimsare made with a hollow section,and junk can collect in this hollowarea causing a rattling.

Housing End CapsIf there seems to be a creaking

when the handlebars are turned,inspect the housing end caps wherethey enter the frame. These endcaps are often metal, and maycreak inside the frame fitting as thehousing is moved side to side.Lubing is a temporary fix. It issometimes possible to shim the capfor a tighter fit.

FrameIt is possible non-drive train creakswill masquerade as coming fromthe drive train. After checking otherpossibilities, check the frame itselffor problems. A crack in a weld or aglued joint that is separating can

also cause a creaking sound. If yoususpect a crack, stop riding the bikeand take it to a professional forfurther evaluation. The imagesbelow show a crack above thederailleur mount, a bonded bottombracket shell separating, and a forkcrown cracked. None of these bikeswere crashed or wrecked. Once acrack has developed, repair isdifficult and is often practicallyimpossible.

Crack at right rear dropout. Likelycause is simply fatigue.

Failure of seat tube at derailleurmount

A carbon fiber frame, with bottombracket shell coming unbonded,resulting in creaking under load

Fork crown failure above brakemount hole

SaddleThe saddle may also be loose onthe seat post, causing a creak asthe saddle rails move and rock.Check security of the saddle railbinder bolts. The seat post can

move slightly in the frame seattube, especially in the fit inside theframe is marginal. Knurling thepost, or even cutting off excess postmay help.

HeadsetThe headset connects the mainframe to the fork and front wheel.Some headsets rely on a tightpressed fit on parts into the frameor fork. If the fit is not properly tightthe parts may move and creakwhen stressed. In some cases thefit can be improved using a"retaining compound". It may bebest to consult a professional for

this repair. For more on headsetssee Threadless Headsets orThreaded Headsets

Stem and HandlebarsA loose stem or bar bolt may alsocause a creaking sound. If the boltsthreads are dry and withoutlubrication, they may not secureproperly. Remove bolt, grease thethreads and under the bolt head,and re-secure. Some handlebarsuse a center section that is presson, called a sleeve. This sleeve maybecome loose with use, and maybegin to creak. Replacement is thebest repair in this case. You may try

a penetrating thread lockingcompounds if you have one, but it islikely to keep creaking. A centersleeve is seen in the left imagebelow. In the right image below,the bar had no center sleeve.However, the bar developed a crackwhere it was held by the stem. Acatastrophic failure was imminent.

Rear CogsThe rear cogs are not a likely

source of a creak, but they shouldbe checked in the interest ofthoroughness. For cassette cogs,check security of lockring. For moredetail see Cog Removal andInstallation. Inspect teeth for burrsand wear, which may cause a popnoise rather than a creak.

Headset Service

Threadless HeadsetServiceThreadless-type HeadsetRemoval, Installationand AdjustmentTypical Tools and Supplies Needed:

Hex Wrenches, for stemremoval: AWS series.

Race Remover, RT-1 or in somecases the RT-2

Headset Press, HHP-2 or HHP-3 .

Crown Race Puller, CRP-1. (otheroptions describe in procedure

below)

Crown Race Installer, CRS-1. For1.5 inch forks us the CRS-15

Degreaser, CB-2

Measuring Caliper

Rags

This article will discuss removingthe old headset, installing andadjusting a new threadless headset.See also related articles:

If you are confident the headset isproperly installed and lubricated godirectly to adjustment.

Bearings on a bicycle allow the

parts to rotate relative to oneanother. The headset allows thefork to turn smoothly while riding.Bicycles, and all two wheeledvehicles, make small selfcorrections in steering whiletraveling forward. If the headset ispitted or worn, these correctionsare not made smoothly andhandling suffers. Very wornheadsets tend to "lock up" whenthe front wheel is pointing straight.Pick up the front of the bike, andgently swing the handlebars backand forth from center. Pitting in thecups will cause the headset to stickas it passes through center position.

A pitted headset should bereplaced. New headsets are pressedinto the frame and fork.

All bearings on a bike have somefriction as they rotate. This isnormal and does not affect the ride.Better quality bearing surfaces areground smoother and will have lessfriction and resistance to turning.Adjustable type bearing systemsuse two opposing races which canbe moved relative to one another.If the adjustment is too tight therewill be too much pressure on thebearing surfaces and balls and thesystem will quickly wear out. If theadjustment is too loose there will

be movement or "play" betweenthe parts. This will cause a knockingin the bearing surfaces and againthey will wear out prematurely.Generally, the bearings should beadjusted as loose as possiblewithout play or knocking in thesystem.

The upper and lower bearingsurfaces are connected by thesteering column. The two bearingsurfaces need to be parallel in orderto operate smoothly. If the upperand lower surfaces of the head tubeare not cut parallel, the bearingswill tend to bind as the fork isrotated. This can lead to premature

bearing wear and a less thandesired adjustment. The head tubecan become deformed by weldingor simply less than adequatemanufacturing techniques. Thebase of the fork steering columnshould also be cut square to thefork. If it is not properly machined,the fork crown race will not sitsquare to the steering column andwill add to the binding effect. Thehead tube can be machined (faced)so the surfaces are parallel by usingthe HTR-1 Head tube and RacingTool. The fork can be machinedwith the CRC-1 Crown Race Cutter.This process is best left to

professional mechanics.

Threadless headset bearings areheld secure by the stem. The upperadjustable bearing race will slide upand down on the steering column.The stem binder bolts hold thestem secure on the column, whichkeeps the race from moving. Toadjust the race, the stem must firstbe loosened. There is a cap in thetop of the stem that will applypressure to the race when the stemis loose. A typical threadlessheadset on the bike, and thevarious parts are seen below.

Headset Removal1. If possible, disconnect cables

shift and brake levers. Loosen

stem and remove bars andstem from steering column.

2. NOTE: If you are not removingbars completely, use care notto kink or damage housingwhen hanging bars on bike.

3. Remove any washers/spacersfrom steering column.

4. Pull fork from bike. It may benecessary to use mallet andtap top of steering columndriving fork downward. Oncefork is driven down as little as25mm (one inch), lift fork backup and remove center conefrom adjusting race. Remove

fork.

5. Note orientation of bearingretainer (if any).

6. Install Park Too RT-1 Race Toolwith small side first upwardthrough the bottom of theheadset cups. Squeeze sides ofprongs and pull tool fully intohead tube. Do not press withhand on bottom of tool, asprongs will close and pinchflesh. A clicking sound will beheard as tool engages headtube cup.

7. Use a hammer at end of RT-1and drive cup from head tube.Use care as cup approachesend of tube, as tool may fall toground on last blow of thehammer.

8. Place RT-1 with small end firstthrough remaining cup andremove.

9. Remove fork crown race fromfork. Use the Park Tool CRP-1.For specific use of CRP-1 seeCrown Race Removal.

10. An optional procedure to theabove is to drive the race offusing a punch and hammer. Insome cases this may scar thefork and crown race.

Installing HeadsetBearing RacesHeadset bearing races are held by

an interference fit into the headtube. An interference fit occurswhen parts are held together byinternal and external surfacesforced together. There must be aslight diameter difference betweenthe two pressed surfaces. Typically,the pressed headset race outsidediameter should be between 0.1mmand 0.25mm larger than the headtube inside diameter. When thecups are pressed, the head tube willflex and enlarge slightly to allowthe cups to press. This tension iswhat keeps the cups tight in theframe.

Use a caliper to measure the

outside diameter of the cups. Next,measure the inside diameter of thehead tube in two places, each 90degrees from the other. Averagethe two reading. If the head tubemore than 0.25mm smaller than therace, it may be reamed using theHTR-1 Headtube Reaming andFacing tool. If the race is between0.01mm and 0.09mm, a differentheadset with a larger press raceshould be used. It is also possibleto use a retaining compound suchas Loctite® RC609. If the race isequal to or smaller than the headtube, a different race should beused. See discussion of press fit

standards below.

The fork bearing race is pressed tothe fork crown race seat. The forkrace is smaller than the crown raceseat. It is the race that expands asit is pressed. Races are commonlymade of bearing steel, which tend

to be very hard and brittle, and donot expand to the same tolerancesas the head tube. The crown raceseat should larger then the race by0.1mm to 0.15. Much moredifference may stress and crack thebearing race. When the crown raceseat is too large for the fork crownrace, it may be milled smaller withthe CRC-1 Crown Race Cutter. If thecrown race seat is only slighltylarger than the race, 0.02 to0.09mm, use a retaining compoundsuch as Loctite® RC609. If thecrown race seat is equal to or evensmaller than the race, use adifferent race. See discussion of

press fit standards below.

Pressing Headtube CupsThis discussion will assume use ofthe HHP-2 Headset Press and theCRS-1 Crown Race Setter.

1. Determine the acceptability ofthe headset press fit asdescribed above.

2. Adjust threaded press plate ofHHP-2 until top is flush withend of hex shaft thread

3. Remove sliding press plate andinstall cups onto guides. Guidesare used to maintain cupalignment while pressing. Cup

guides fit most 1-inch and 1-1/8-inch standard headsetcups. Before using cup guide,insert guide into cup. If guideappears to jam or is a tight fit,DO NOT use cup guides for thatparticular headset cup. Do notuse cup guides #530-2 ifguides press on any pre-installed cup-bearing unit (ex.Chris King® headsets). Forheadsets not fitting #530-2 cupguides, simply press usingthreaded press plate andsliding press plate. Pressure onthe outer rim of aluminumhead cups may visually scar the

cups. If not using the guides, itcan help to press one cup at attime.

4. Place upper headset cup on topof head tube. Hold one cupguide onto top threaded pressplate and lower assemblythrough top headset cup.

5. Install second cup guide ontosliding press plate, and placelower cup onto guide.

6. Engage sliding press plate ontohex shaft, and push plateupward until headset cupmeets head tube. Releaselever. Sliding press plate levermust be engaged in one of

seven hex shaft notches. Pulldownward on lower press plateto test engagement.

7. Turn handle clockwise slowly

and inspect alignment of cupsas cups enter head tube.Continue and press cups fullyinto head tube. If threadedpress plate has bottomed onthreads of hex shaft, turnthreaded press plate counterclockwise until it is again flushwith top of threads. Re-engagesliding plate to a higher notch,and continue to press cups.NOTE: Never use a "cheaterbar" to extend leverage ofhandles. If cups will not pressusing handles, other problemsare present and should beaddressed.

8. NOTE: If the headcup has pre-installed cartridge bearings,check that any guide will notpress directly on the rotatingbearing. For these types ofcups, press only with the flatplates of the headset press.Press only one cup at a time.

9. Inspect for full seating wherecups meet frame. A gapindicates incomplete pressing,as seen below.

10. Remove HHP-2 from bike.Unthread handle 1 turn, presslever of sliding press plate andremove tool from bike.

Pressing Fork Crown

RaceThe fork crown race must bepressed to the fork crown.Determine acceptability of press fitas described above. Place race onfork crown and select mostcompatible CRS-1 insert. Place tooland insert over fork. Use hammerand strike top of tool until race fullyseats. The sound will change as itseats. Inspect sides of race forseating.

Installing the StarFangled NutThe threadless headset is adjust bypressure from the top cap. The

adjusting bolt threads into the "starfangled nut". For nut installation,see Star Fangled Nut Installation.

Headset Assembly

If the headset is using bearingretainers, check the orientation ofthe retainers before installing.Inspect the metal cage that retainsthe ball bearings. The cage trapseach ball with a hook. Look for theopen side of the ball retaining hook.This open side of the cage shouldface the cone shaped race, not thecup shaped race. If in doubt, installthe cage, and place the race insideand turn. If the cage is correct, itwill feel smooth. If the cage isupside down, the cage retainer willrub on the race and it will feeldifferent. Reverse the cage and testagain.

It is also possible to replaceretainer ball bearing with loosebearings. Grease cups to holdbearings, and place balls into cupshaped races. Leave a wide gap the

size of two ball bearings, do notattempt to fully fill cup.

1. Grease bearing retainers andbearing race cups. NOTE: Donot grease steering column.

2. Install bearing retainers intocup shaped races.

3. Place fork through head tube.

4. Install adjusting race and racecentering cone onto column.Press centering cone intoadjusting race to help holdfork.

5. Install spacers and accessoriesas appropriate.

6. Install stem and snug stembolts. Check for adequateclearance from top of columnto top of stem. Add spacerunder stem if necessary. Imagebelow is view of steeringcolumn and stem. There is agap between stem and top ofcolumn.

Headset Adjustment -Threadless TypeThreadless headsets work on thesame principal as threadedheadsets. The bearing races need

to press against the bearings. Thebolt in the top cap will put pressureon the stem, which presses onwashers below the stem, whichpress on the bearing races, whichpress against the bearings.

NOTE: The cap and bolt at the topof the stem do not secure the stemonto the steering column. The boltor bolts on the side of the stemkeep the stem from moving oncethe adjustment is made. The cap isused for bearing adjustment only.

Begin by removing the adjustingbolt in the center of the steeringcolumn. Next, remove the top cap.There may be a star-shaped nut or

other fittings inside the steeringcolumn. The bolt threads into thisfitting and pulls on the fork againstthe headset bearing surfaces, whichacts to tighten the adjustment.Note the height of the steeringcolumn relative to the stem. Itshould be about 3mm (1/8") belowthe level of the stem. The stemneeds to press down on the spacersin order to adjust the bearings. Ifthe steering column is level withthe top of the stem, another spaceris needed below the stem.

1. Remove bolt and top cap toinspect steering column.Lubricate adjusting bolt and re-

install cap and bolt by handonly. DO NOT TIGHTEN.

2. Loosen stem bolt(s) that securestem to the steering column.Lubricate these bolts if they aredry. NOTE: DO NOT LUBRICATEINSIDE STEM OR ON STEERINGCOLUMN SURFACE.

3. Wiggle the stem side to side tosee that it is loose. If the stemis jammed or rusted frozen tothe steering column, noadjustment can be made.

4. Align stem straight to wheeland gently secure the top bolt.Stop when any resistance is

felt.

5. Tighten stem bolt(s).

6. Check for play by pulling backand forth on fork. Turn thehandlebars in differentdirections while checking forplay. There may be play at thisearly setting. Use care whengrabbing suspension forks,because the legs may haveplay. Grab upper portion offork.

7. To adjust bearings, LOOSENSTEM BOLT(S).

8. Turn adjusting bolt in centercap only 1/8th turn clockwise.

9. Secure stem bolts, check forplay again.

10. Repeat adjustments as aboveuntil play disappears.Remember to loosen stembolts before turning adjustingbolt in cap.

11. Check alignment of stem andtighten stem binder bolts fully.

NOTE: Another test of play is toplace the bike on ground and grabthe front brake tightly. Pressdownward on the handlebars androck the bike forward and back. Aknocking sensation may indicate aloose headset. In effect this does

the same thing as grabbing andpulling on the fork. However, playin the brake caliper arms may alsocause a knocking. Front suspensionforks may also have play in thelegs, which can cause a knocking.Ifthe adjustment seems very tight,there may be other problems in theheadset. Bearing surfaces may beworn out, or the ball bearingretainers may be upside down, or aseal may be improperly aligned. Ifplay always seems present nomatter the adjustment, the steeringcolumn may be too long for thestem and top cap. Add spacersbeneath stem in this case.

Bearing Adjustment and"Feel"Bearing surfaces are made fromhardened steel. The surfaces arecut typically by grinding. Round ballbearings roll on the curved surfaceof the cup and cone. Even thehighest quality bearing surfaces willhave slight grinding marks. In theleft image below is a high qualitycone magnifed two hundred times.Notice the parallel marks from thegrinding stone. Also note a slight pitfrom wear. The right hand image isa bearing magnifed the sameamount. It does show some surface

marking, but is generally smootherthan the cone or cup. Bearingsurface smoothness will varybetween manufacturers andbetween models. Some bearingsystem will simply "feel" smootherbecause they are smoother. This iswhy it is difficult to adjust by usinga subjective feeling of smoothness.Generally, adjust bearings for theloosest setting that has no knockingor play, regardless of this relativesmoothness.

Headset SizingStandardsThere are several standards forheadsets found on bicycles.Headsets are named by thediameter of the steering column,not by the press diameter of the

cups. For example, a "one-inch"headset is for bikes with one inchdiameter steering columns.

There are three different headsetstandards using one inch forks. Twoare common, the JIS and "ModernEuropean" standard. The older BMXstandard is seen less and less. TheJIS and "Modern European"standard differ only in the diameterof the press fit. The two standardsare NOT interchangeable, eventhough both use 1" x 24 TPIthreading. A bicycle that wasmachined to the JIS standard maybe reamed and cut to the "ModernEuropean" standard. The head tube

would be ream to 30.0mm ID andthe fork crown seat cut down to26.5mm. A bicycle that was madein the "Modern European" standardcan not use a JIS headset.

Below is a list of "conventional"headset standard sizing. There arenow in use other standards anddesigns, see also HeadsetStandards and Nomenclature.

One-inch Japanese IndustrialStandard (JIS)

Common on many Asianmanufactures bicycles, bothroad and MTB

Fork column outside diameter-

25.4mm (1")

Head cup race OD- 30.0mm

Acceptable head tube ID range-29.75mm to 29.9mm

Fork crown race ID- 27.0mm

Fork crown seat OD acceptablerange- 27.1mm to 27.2mm

Threadless stem diameter-25.4mm (1-inch)

One-inch "Modern European"Standard

Many road bike and some MTBbikes

Fork column outside diameter-

25.4mm (1-inch)

Head cup race OD-30.2mm

Acceptable head tube ID range-29.9mm to 30.1mm

Fork crown race ID- 26.4mm

Fork crown seat OD acceptablerange- 26.5mm to 26.7mm

Threadless stem diameter-25.4mm (1-inch)

1-1/8" Oversized

Many MTB bikes, tandems, someroad bikes, BMX

Fork column outside diameter- 1-1/8" (28.6mm)

Head race cup OD- 34mm

Acceptable head tube ID range-33.75mm to 33.9mm

Fork crown race ID- 30.0mm

Fork crown seat OD acceptablerange- 30.1mm to 30.2mm

Threadless stem diameter-28.6mm (1-1/8 inch)

1-1/4 inch Oversized

Tandems, some MTB bikes

Fork column outside diameter- 1-1/4 inch (31.8mm)

Head cup race OD- 37mm

Acceptable head tube ID range-36.75mm to 36.9mm

Fork race ID-33mm

Acceptable fork race seat OD-33.1mm to 33.2mm

Threadless stem diameter-31.8mm (1-1/4 inch)

Threadless BMX

BMX threadless is same as 1-1/8above.

Star Fangled NutInstallationTypical Tools and Supplies Needed

Threadless Nut Setters TNS-1 orTNS-4

Hammer such as the HMR-4

Threadless headsets are adjustedby pressure on the top bearingrace. Pressure is applied when thebolt in the top cap is tightened. Thestem bolt(s) must be loosened,which makes the stem effectively aspacer during the adjustment. Thebolt is threaded into the starfangled nut which be fitted into the

inside of the fork column. The starnut is designed not to pull upward.In otherwords, it is designed not tobe removeable.

The star fangled nut outer diameteris slightly bigger than the insidediameter of the fork column. Thisallows the flanges to bite into the

fork walls and hold it tight.

Star Fangle NutInstallation with TNS-4The TNS-4 is designed to help guidethe star-fangled nut straight as it ispressed into the inside of thesteering column.

Thread the star-nut onto thethreaded stud inside the TNS-4.

The convex surface will faceoutward of the tool, and face thesteering column.

Place the TNS-4 over the top of thesteering column. The inner mandrelwill rise upward and the outerhousing is slid over the column.

Hold the TNS-4 straight and in linewith the steering column.

Strike the top of the TNS-4 with ahammer to drive in the star fanglednut.

Continue driving the nut util thedrivr meets the outer portion of thetool. Unthread the hanlde from thefork. Nut is installed.

Star Fangle NutInstallation with TNS-1Mount the nut with concave sidetoward tool thread. Hold TNS oversteering column and tap on top onTNS with ball peen hammer. Hold

tool aligned while striking TNS.

The TNS places the nut about15mm (9/16") below the top of thesteering column. This allows theadjusting bolt to thread fully intothe nut for adjustment pre-load.

It can also help maintain alignmentto use the stem as an alignmentguide. This technique works ONLY ifyou use the newer longer TNSmodels. Install stem onto column.Engage so most of the stem sticksup above the column. Do not

tighten any upper pinch bolt. PlaceTNS with nut inside stem andcolumn and tap downward.

Removing the nutThe star fangled nut is basicallydesigned not to be removeable. If it

is necessary to install another nut,simply use a punch and drive thefirst nut down until deeper than thenew nut will sit. It is not necessaryto completely remove the old nut. Itis also possible to drive the old nutcompletely through the column andout the bottom. This will make thenut unuseable. It can also work todrill out the center of the nut, andthen tap out the remaining pieces.

Screw Replacement inTNSThe TNS-1 and TNS-4 use areplaceable (6mm x 1mm)setscrew, part #822. Use a small

amount of removeable threadlocking compound on the threads ofthe new screw. Use 3mm hexwrench in end of screw, and threadinto body, leaving about 10 threadsexposed.

Expansion PlugInstallationAnother option for threadlessheadsets is the "expansion plug"systems. These insert inside thesteering column and then expandand jam against the inside walls.This system is especially popularwith the carbon steering columns.

A typical expansion plug system

consist of an expandable sleeve.There is a cone at the top andbottom, and a hollow bolt passesthrough the sleeve. As thisexpansion bolt is tightened, itdraws together the two cones andthis expands the sleeve. As withmost all threaded fasteners, greaseor oil the threads. The headsetadjusting cap and bolt then fit intothe top of the expansion plug.

Install the assembled expansionplug into the steering column.

Secure the expansion plug

Install top cap and headsetadjusting bolt into expansion plughollow bolt.

Finished headset top cap.

Chain repair andservice

Chain Installation-derailleur bikesTypical Tools andSupplies

Chain Tools-CT-2, CT-3, CT-5 orCT-6

Repair Stand to hold bike(optional but nice)

Special Replacement pin forShimano® or special link forCampagnolo® chains asappropriate

CL-1 Synthetic Blend Chain Lube

Rags

This article will discuss the removaland installation of chain onderailleur bicycles. See also relatedarticles:

Chains are made up of a repeatingseries of inner plates, a roller, achain rivet (also call a "pin"), andouter plates. The chain rivetpresses into both outer plates, butthe rivet slides freely through theinner plates and the roller. Chainshave a small amount of play ateach link, even when brand new. Asa chain is ridden, it wears therivets, and the play at each linkincreases. This is sometimes called"stretch", although the plates do

not literally become longer. A wornchain will not engage the cogscorrectly, and will eventually slipover the cog teeth when pressure isapplied. To check chain wear, usethe CC-2 Chain Checker, or the CC-3. New chains can be fitted to thebicycle, although new chains arelonger than required and must beshorted to the correct length.

To install or remove a chain, achain tool is required. Chain toolsare made up of a driving pin and a

cradle to hold the chain-roller.Some models have two cradles. Theprimary cradle supports the chainplate for pressing the chain rivet inand out. The tight link cradle is onlyfor fixing a tight link. The serviceprocedure will vary between brandsof chains. Always check theinstallation instructions on a newchain.

The Park Tool CT-3 and CT-5 aredesigned for use with 3/32"derailleur type chain. The CT-2 willservice both 3/32" and the wider1/8" chain. The CT-7 will work on3/16 inch chains and 1/8 inchchains common on freestyle bikes.The CT-7 will not work on derailleur

chains.

When installing a chain, keep inmind that most chain failure is dueto one of the pins being improperlyinstalled. Modern chains are verynarrow, and even a small amount ofmisalignment in rivet as it sits inthe side plates could cause thechain to break under load. Checkeven new bikes by viewing eachand every pin for protrusion at theside plates.

Also inspect any pre-mounted chain

for bent side plates or missingrollers. Inspect side plates fordeformity or other anomalies.

Procedure forShimano® ChainSome chains, including Shimano®,use chain rivets which are peened.

This creates a "mushroom" effect atthe ends of the rivets, which addsto the strength of the chain sideplates. When a rivet is pressedeven partially out, this peening issheered off on the side pressed bythe chain tool. If this rivet werereused, it would create a weak linkat that rivet. In the image below, aShimano® rivet is shown in anoptical comparator, which magnifiesthe rivet. The original peening isseen at the bottom of the rivet. Thetop of rivet has the peeningsheered off. This top section waspushed through the outer chainplate.

Shimano® chains use a specialconnecting rivet when the chain isinstalled new or when one isremoved and re-installed. Thisconnecting rivet has special flaringthat is guided in by a long tapered

pilot. The pilot is then broken offbefore riding. Only Shimano®brand chains should use theShimano® connecting rivet.

The 7 and 8 speed chains use ablack connecting rivet. Thenarrower 9-speed chain uses asilver-colored connecting rivet. The Shimano ® CN-7800 chain for10-speeds uses a silver coloredrivet with an extra-machined linefor identification on the pilot. TheShimano ® CN-7801 chain for 10-speed sprockets uses a connectingrivet with three machinedidentification lines. The 10-speedchain rivets are notinterchangeable.

A= 7 or 8 speed connecting rivetB= 9 speed connecting rivetC= 10 speed connecting rivet formodel CN-7800

D= 10 speed connecting rivet formodel CN-7801

Shimano® ChainService Procedurea. Select a chain rivet identical toadjacent rivets. Do not select apreviously installed connectingrivet, or a rivet immediatelyadjacent to a connecting rivet.Avoid selecting the specialconnecting rivet, and avoid anyrivet that looks different from theothers.

Some Shimano® chains use a rivetaround the entire head.

b. Place the roller of the chain fullyin the primary cradle of the chaintool.

c. Turn the chain tool pin until itcontacts chain rivet and stop. Noteposition on handle.

d. Drive rivet from chain plates. Some models of chain tools maynot fully drive rivet from chain.

Use connecting rivet to finishdriving old rivet from chain.

e. Back out chain tool pin and liftchain out of cradle.

f. Grab chain on either side ofprotruding rivet. Flex chain towardthe protruding chain rivet then pullon chain to separate.

g. Pull on non-rivet end to removechain from bicycle.

To reinstall the special connectingrivet:

a. Reinstall chain on bike withprotruding chain rivet facing awayfrom you. The design of theShimano ® chain requires that theconnecting rivet leads the chainplate as it engages the sprockets.

b. Open outer plates slightly andinsert inner plates. Align protrudingrivet with hole in inner plate.

c. Lubricate connecting rivet andinstall into chain rivet hole, withtapered end first. Replacement rivetwill protrude outward towardmechanic.

d. Back chain tool pin into tool bodyto make room for replacementchain rivet.

e. Place roller into primary cradle ofchain tool.

f. Drive replacement rivet intochain. Replacement rivet will drive

out original rivet if it was left inchain. Continue to drive until chaintool pin is almost adjacent to outerside plate.

g. Remove the chain from tool and

inspect rivet. Non-tapered end ofreplacement rivet should protrudesame as any neighboring rivet.Press further if necessary. Imagebelow shows a protruding chain pin.Repair as necessary.

h. Break off pilot of connectingrivet. With Park Tool, use groove ofbody of CT-3 or CT-5 and twist pilotsideways. Pliers can also bemusedto break rivet. Inspect rivet againand press further if necessary.

i. The connecting chain rivet shouldnot be used again to separate thechain. Re-using same rivet holewears plate holes and may weakenchain. Use other original rivets forfuture chain cutting.

j. Inspect for tight links and repair

as necessary. Shift to a gear thatwill relax derailleur cage. Pedalbackwards and note any hoping orjumping of chain as it passesthrough pulleys. See also Tight LinkRepair.

Re-useable Rivet-typeChainsThere are several brands of chainthat are serviced by pressing out arivet partially, then re-pressing thesame rivet to re-install. Check withthe manufacturer"™s literaturewhen in doubt.

a. Inspect chain for "master link", ifany. Disengage master link

according to manufacturer"™sinstructions.

a. If no master link is present, placea roller of the chain fully in theprimary cradle of the chain tool.

b. Drive chain-tool pin until itcontacts chain rivet.

c. For most non Park Tool brandchain tools, turn handle 5 completeturns. Use care not to drive outchain rivet. For Park Tool CT-3,drive T-handle until it is stopped byC-clip. For Park Tool CT-5, drive T-handle until body stops screw.

d. Back out chain-tool pin and liftchain out of cradle.

e. Grab chain on either side ofprotruding rivet. Flex chain towardthe protruding chain rivet then pullon chain to separate.

f. Remove from bicycle by pulling onrivet end of chain.

To reinstall the chain rivet:

a. Re-install chain on bike withprotruding rivet facing towardmechanic.

b. Open empty outer plates slightlyand insert inner plates. Push innerplates until hole aligns with chainrivet.

c. Back chain-tool-pin into tool bodyto make room for chain rivet.

d. Place roller into primary cradlewith chain rivet facing chain toolpin.

e. Drive chain rivet back into chain,taking care to center rivet exactly

between both outer plates. If morechain rivet appears on one side ofouter plate than other, push rivetuntil it is evenly spaced.

f. Inspect for tight links and repairas necessary. See Tight Link Repair.

Master-Links inDerailleur ChainsSome chain manufacturers offer a"master-link" to join the chain. Besure to read the manufacturersdirections. Typically, the bicyclechain ends must have inner plateson each end. In other words,neither chain end has an outerplate with a rivet. The link comes in

two pieces.

Install one piece through inside faceof chain, and install second piecethrough outside of the other chainend. Engage the two pieces so linkrivet mates to link plate hole. Pullchain to lock the link. The bestmethod to do this is to movemaster link to top section betweenrear cogs and front chainrings andpress hard on pedals. This insuresthe link is fully locked. Inspect linkbefore riding the chain.

Note: Some master links arereusable, while others aredisposable and should be replacedafter each removal. Checkmanufacturer"™s specifications.

Campagnolo® 10-speedChainsThese chains currently use a specialsystem called the HD-Link. Itconsists of a short section of linksand two special piloted rivets.When determining chain length, you

must deduct an additional amountof chain equal to this section.

Both ends of the special link sectionare out plates, and these mustattach to the inner plate section ofthe chain. Install the pilot into thechain rivet and place this into thechain. Engage pilot and rivet so thatthe rivet faces the inside of thebike, toward the spokes. The pilotis then pushing outward, away fromthe spokes.

It is especially important with thePark Tool chain tools to pressdownward on the chain at rivet tokeep in fully engaged. In the imagebelow, the thumb presses down onthe chain.

After the rivet is fully pressed,remove the pilot simply by pullingoutward.

It is best to clean the Campagnolochain in place on the bike ratherthen remove it, and reinstall. If youare removing the chain andinstalling it to a different bike,select a section of chain other thenthe HD link set. Do not re-use a linkonce the special rivet has beenused. Re-pressing in the same outerplate will weaken the press fit andconsequently weaken the chain.

Installing ChainThrough DerailleursThe chain is routed through the rearand front derailleurs before beingjoined. It is best to first determinechain length before installing chain.

a. Shift front and rear derailleurunder smallest rear cogs.

b. Pull back on rear derailleur andfeed short section of chain over thetension pulley and straight to theguide pulley.The design of theShimano ® chain requires that theconnecting rivet leads the chainplate as it engages the sprockets.For Shimano ®, feed the outer

plate end of the chain onto thepulleys.

NOTE: Chain should not drag onany part of the derailleur cage.

Image on left shows correct routing.Image on right shows incorrectrouting.

c. Pull chain behind rear cogs andthen forward toward front rings.

d. Hold a short section of chain andfeed chain through front derailleurcage. Turn cranks slowly as youfeed chain onto smallest ring.

e. Joint chain at lower sectionbetween front and rear cogs. Usecorrect procedure according tobrand of chain. See process above.

f. After installing the chain, checkfor any tight links. Before riding thebike, check the derailleuradjustment.

Chain Length SizingTypical Tools andSupplies

Chain Tools-CT-2, CT-3, CT-5 orCT-6

Repair Stand to hold bike(optional but nice)

Special Replacement pin forShimano® or special link forCampagnolo® chains asappropriate

Tape measure (optional, for"Equation Method" only)

Chain Lubricant CL-1 Synthetic

Blend Chain Lube

Rags

Chains for derailleur bicycle shouldbe an adequate length. A chain thatis too long or too short can causeshifting and riding problems.However, the rear derailleur cageshould be long enough to take upslack as the chain is movedbetween the different gearcombinations. This is referred to as"total capacity", and is discussedbelow.

This article will describe threemethods to achieve adequate chainlength. All three methods tend to

yield adequate chain lengths. It isnot necessary to use all threemethods, as one method mayappeal to you and your situation.The first system described is theEXISTING CHAIN method. Itassumes the bike already has achain in place. The second systemis LARGEST COG-TO-LARGESTCHAINRING method, and doesnot require the pre-existing chain.The last system is the EQUATIONMETHOD, and uses simply math todetermine chain length.

NOTE ON REAR SUSPENSION: Ifthe bike has a rear suspensionlinkage, it is usually necessary to

account for the movement of therear hub from the bottom bracket.If the rear hub moves away fromthe bottom bracket, set chainlength is the longest position.Consult the bike manufacturer forcorrect chain length if in doubt.

DERAILLEUR CAPACITY: Thederailleur capacity refers to thederailleurs ability to take up chainslack as the derailleur shiftsbetween different gearcombinations. Some bicycles mayhave sprocket combinations that donot allow the derailleur to take upthe chain slack. In this case, thegearing on the bike exceeds the

capacity of the derailleur. If thederailleur capacity does not matchthe gear sizes on the bike, thechain may appear to fail either the"too long" test or the "too short"test. A chain length cannot be foundthat will pass both tests. In thiscase it is better to size a chain fortoo long rather than too short. Boththe EXISTING CHAIN andEQUATION methods below willsafely size a chain when a bike isviolating the derailleur capacity. Itmay be necessary to avoid gearcombinations that cause problemsin pedaling or shifting on thesebikes.

Chain Sizing-ExistingChain MethodBefore removing the old chain,check the bike for acceptablelength. Cut the new chain relativeto the old chain length.

Shift bike to smallest chainring infront and smallest cog in back.Inspect the section of chainbetween lower derailleur pulleywheel and bottom of smallestchainring. There should not be anobvious sag in the chain. Check alsothat the lower section of chain doesnot rub chain at upper pulley. It isnormal for there be low chain

tension in this position, but thechain should not sag. Sagging inthis position indicates a chain thatis too long.

Too long a chain length sags insmallest cog front and rear. Notechain-to-chain contact at upperpulley.

Adequate chain length will not sag.

If the chain is too long, find thechain rivet contacting bottom ofchainring, and mark the chainring atthis point. Count two chain rivetstoward derailleur, lift this rivet andmove to position of mark. Chain isnow effectively shorter. Check forsag again. Repeat counting tworivets and moving to chainringmark. Number of rivets to shorten

must be an even number (2, 4, 6,etc.) Repeat until chain has novisible sag.

To determine if the chain is tooshort, shift chain to largestchainring and second largest rearcog. Chain will appear tighter in thisposition. Inspect chain for "S" bendas it passes through pulley wheels.Shift slowly and carefully to largestrear cog. If chain appears to jam, itis too short. If chain does shift, butthere appears to be no double bendof the chain at the pulley wheels, itis too short. You will need to addtwo rivet lengths to new chaincompared to the old chain. NOTE:

Do not attempt to lengthen an oldchain by adding new links.

Adequate chain length seen abovein largest sprockets front and back.Note the chain bends at bothpulleys.

Chain length in the two imagesabove short it is too short. Note the

lack of an obvious bend at pulleys.

If the current chain length passesone of the tests above, but fails theother, it is likely the dereailleurcapacity does not match thegearing on the bike. Set the chainlength so it passes the large ring tolargest rear sprocket test. It willthen be the responsibility of theuser to avoid shifting to gearcombinations that cause chainslack.

If a new chain is being installed andthe old chain is the correct length,the new one may be shortened tothe old length before beinginstalled. First, remove the old

chain and lay it on a flat surfacewith the rollers aligned vertically.Pull the chain straight. Lay the newchain next to the old chain in thesame fashion. Make sure the endsof the two chains match, with eithera rivet or no rivet at each end. Thenew chain will appear shorter, sopush the links of the old chain backto match up with the new chain.Locate the matching end rivet onthe new chain with the rivet on theold chain. Add or subtract chainlinks as necessary from inspectionresults stated above and cut thechain at this point.

Chain Sizing - Largest

Cog and LargestChainring MethodAn alternative method fordetermining chain length for newchains is to use the largest sizesprockets on the bike. It is easiestto size the chain without threadingit through the derailleur.

1. Remove the old chain.

2. Shift the front derailleur overthe largest chainring, and therear derailleur on the smallestcog.

3. Thread the new chain throughthe front derailleur. It is not

necessary to thread the chainthrough the rear derailleur atthis point. Simply wrap thechain around the largest frontchainring and around thelargest rear cog.

4. Pull the chain tight, and notethe closest rivet where the twocould be joined. Keep in mind achain can only be joined bymating inner and outer plates.

5. From the closet rivet, lengthenthe chain by counting over anadditional two rivets (twolinks), which is a distance ofone-inch. Cut the chain at thispoint.

6. Remove the chain from the bikeand thread it through bothderailleurs and join the ends.

MASTERLINK NOTE: If the bikechain uses a "master link", it isnecessary to account for the link.Install one-half of the master linkon one side of the chain. Size thechain by cutting the other end ofthe chain.

Chain Sizing byEquationBicycle chains consist of inner andouter plates. It is only possible tojoin inner plates to outer plates.Because of this, chains can only beconnected at whole (integral) inchincrements. For example, somederailleur bike chain could only be51, 52, 53 inches, etc. Chains

cannot be cut to 52-1/4", 53-1/8",or even 52-1/2". It is possible todetermine chain length fromindustrial drive train equations, andthen cut the chain before installingit on the bike.

Begin by counting the number ofteeth on the largest front sprocketand largest rear. These numbersare often printed right on thesprockets and cogs. Next, measurethe distance between the middle ofthe crank bolt to the rear axle. Thisis also the chain stay length.Measure to the closest 1/8", andconvert this to decimal form. Asimple chart below will assist this

conversion.

Fractional conversion to decimal for1/8" measurements: 1/8" = 0.125"1/4" = 0.25" 3/8" = 0.375" 1/2" =0.5" 5/8" = 0.625"3/4" = 0.75"7/8" = 0.875"

For most bicycles, a relativelysimple chain length equations maybe used. For bicycles with extremedifferences in chainring sizes andshort chain stays, the more rigorousand complete equation may beused. This is discussed later in thisarticle.

SIMPLE EQUATION: L = 2 (C) +

(F/4 + R/4 + 1)

L = Chain length in inches. Roundthe final result to closest whole inchfigure. C = Chain stay length ininches, measure to closest 1/8".Use chart below to find decimalmeasurement.F= Number of teeth on largest frontchainring.R= Number of teeth on largest rearcog.

Example: A bike has a 42-32-22front chainring set up. Use only the42 for the equation. The rear cogset has 32 tooth largest cog. Thebike measures 16-3/8" from thecenter of the rear axle to the center

of the crank bolt. The decimalequivalent for 16-3/8" is 16.375inches.

L = 2 (16.375) + (42/4 + 32/4+ 1)

In the example above, thisbecomes 32.75 + 10.5 + 8 + 1 =52.25 inches. Chains cannot bejoined at 52.25 inches, so thislength is rounded to 52 inches.

For this system, round up from 0.5.For example, a chain length figuredto be 55.5 would be rounded to 56inches.

To measure the new chain, lay it ona flat surface with the rollers andplates aligned vertically. Pull oneach end to straighten out thechain. Measure from either end.Remember, you can only shortenthe chain at whole inch increments.If the chain uses a master link,install it on one of the chain forpurposes of measuring, andmeasure including the master link.

Rigorous Equation

Examples of bikes using therigorous equation would be a trackbike with a large front ring, perhapsa 55 tooth, and a small rear cog,such as a 11 tooth. Additionally, torequire the rigorous equation, thebike would need a very short chainstay, such as 15 inches or under inlength. As the front and rearsprockets differ more in size, thechain must diverge more off a linerepresented by the chain stay. Thisis the hypotenuse of a triangle,which can add to the chain length.Again, it is only a concern in veryextreme cases.

For an example of the rigorousequation, assume a one speed bikehas a 15 inch chain stay, a 58 toothfront ring and an 11 tooth rearsprocket. For one-speed bikes,eliminate the "1" at the beginningof the equation. This is the extrainch added by derailleurmanufacturers when sizing chain.The short equation yields ananswer of 47.25 inches, whichshould be rounded to 47 inches.The rigorous equation yields ananswer of 48.17 inches, which isrounded to 48 inches. The shortequation would be an inch tooshort. This again is an extreme

situation. Even in this one-speedexample, if the chainring is reducedto a 55t, the two equations comeup with the same answer.

Tire and InnerTube Service

Inner Tube RepairTypical Tools and Supplies Needed

1. Pre-glued Patch Kit such as theGP-2or Vulcanizing Patch Kit VP-1

2. Floor pump PFP-4 or PFP-3,hand pump PMP-3, PMP-4,PMP-5, or air compressor.

3. Useful items- marking pen,rags, alcohol solvent

This article will discuss the patchingof bicycle inner tubes. Both the pre-glued patches and the vulcanizingpatches will be reviewed. See alsorelated articles: Wheel Removal

and Installation and Tire and TubeRemoval.

The GP-2 Super Patch Kit uses pre-glue patches. There is no tube ofglue to leak or dry up.

To fix a flat, first locate the hole inthe inner tube. If possible, re-inflateinner tube to at least twice thenormal width. Inspect for air leaksby holding tube close to thesensitive skin of lips or by holdingtube near your ear to hear leaks.Move the tube around itscircumference. If you find one hole,keep looking for more. Inspectinside the tire for sharp objects orglass. Also inspect the rim strip in

the rim. It should not have anyholes around the spoke holes andshould fully cover the holes.

If you plan to repair the inner tube,use a marking pen to mark hole.Make four marks, one to each sideof hole. Do not mark close to hole,as the mark may be sanded off.

To Patch an Inner TubeUsing the GP-2 SuperPatch

1. Locate hole marked duringinspection. Using fine emerycloth or sandpaper, clean thetube by lightly abrading area

around hole. Excessive sandingor heavy pressure can causegrooves in the rubber, whichmay lead to patch failure.

2. If available, wipe the area withclean rag and alcohol. Allow itto dry completely.

3. Peel patch from patch backing.Handle patch as little as

possible and by edges only.

4. Center patch to hole and laypatch on tube.

5. Apply pressure to patch toassure seal. Roll patch andtube between thumbs andforefingers.

6. Tube is ready to install. DO

NOT test patch by inflatingtube while outside of mountedtire. This may stretch tubebody and weaken patch bond.

Patching an Inner TubeUsing the VP-1Vulcanizing Patch KitGlue type patches require theapplication of a thin layer of self-vulcanizing glue on the tube beforethe patch is applied.

1. Locate hole marked duringinspection, as described above.

2. Using fine emery cloth orsandpaper, lightly abrade areaaround hole. Abrade an arealarger than patch size.

3. When possible, clean area withalcohol and allow it to drycompletely.

4. Open glue tube and punctureseal. Apply thin coat of glue

and spread evenly around holearea. Spread area of gluelarger than patch size. Use aclean finger or back of patch tospread glue evenly in a thinlayer. Do not apply too muchglue. Glue layer should notappear "glopped" on.

5. Allow glue to dry. This may

take several minutes. Test bytouching only perimeter area ofglue, not where patch willcontact.

6. Peel patch from patch backing.Handle patch only by edges.

7. Center patch to hole and laypatch on tube.

8. Apply pressure to patch,

especially at edges.

9. If possible, maintain pressurefor several minutes.

10. Leave clear plastic cover onpatch, do not peal up.

11. Mount tube inside tire andinflate.

Temporary Repair ofTire with Tire Boot TB-1If the tire has been ripped and thecasing damaged, it may not hold aninner tube. It is possible in somecases to make a temporary repairwith a Tire Boot. A booted tireshould not be considered a

permanent repair. The tire shouldbe replaced as soon as possible.

1. Locate rip in tire. Compare ripto size of tire boot. Tire bootmust completely overlap rip tobe effective.

2. Wipe clean inside of tireadjacent to rip.

3. If using Park Tool Boot TB-1,peal off backing of TB-1.

4. Align patch so edges do notextend beyond tire bead. Ifnecessary, cut boot so it doesnot extend past tire bead.

5. Center patch to rip and presspatch to inside of casing.

NOTE: Always replace rippedtires as soon as possible.

Tire and Tube Removaland InstallatonTypical Tools and Supplies Needed

Repair stand (optional, makesthe work a lot easier)

Tire levers TL-1, TL-4, TL-5, orbody of various take-a-longtools.

Patch Kit such as the GP-2, orVP-1.

Air pump: see Pumps, or aircompressor.

Wrenches for non-quick-releasetype wheels that use outer axle

nuts.

The wheel must be removed toreplace the tube and tire. Ifpossible, begin by mounting bike instand. If no stand is available, bikeshould be laid on its left, non-derailleur, and side when the rearwheel is removed. Do not standbike upright without the rear wheelin place, as this will damage therear derailleur.

1. Rear wheels, shift derailleur tooutermost gear and innermostfront chain ring.

2. Release brake quick-release, ifany. Typical MTB brakes and

road brake quick releasemechanisms are shown below.

3. Release wheel quick-release bypulling quick release leveroutward. Pull outward on end

of quick release skewer lever.If necessary, loosen quickrelease adjusting nut to clearany tabs at end of fork. Forwheels with axle nuts, loosenboth nuts outside of dropouts.

4. Front wheels guide wheel downand out of fork. For rearwheels, pull back on rearderailleur to allow cogs to clearchain. Lower wheel, guidingthe wheel down through brakepads and forward to clear chainand derailleur. Guide the wheelthrough the brake pads and outthe fork ends.

Removing Tire and Tubefrom RimTires can be tightly fitted to therim. Use tire levers to pry tire bead

up and over rim sidewall. Do notuse a screwdriver, knife, or othersharp object, which might damagetire or tube. Fully threaded valveshafts may have a locking nut nextto rim. Loosen and remove lockingnut before deflating.

1. Deflate tire completely. Even asmall amount of air left in thetube can make it more difficultto get the tire off. For bestresults, press downward onwheel while depressing thevalve.

2. Push one bead of tire towardrim center. The tire bead willbe pressed tight against rim.

Pushing it inwards loosens thebead from the rim. Repeat onother bead.

3. Engage one tire lever underbead of tire. Engage secondlever 1-2" (25-50mm) from firstlever then pull both leverstoward spokes to lift bead offrim. Disengage one lever. Move

it two inches (5cm) along therim and engage lever in thebead. Pull lever to lift nextsection of bead off rim.

4. Repeat engaging the lever untilthe bead loosens. Then slidethe lever along the rim underthe bead.

5. Starting opposite the valve, pullinner tube from tire. Lift valvefrom valve hole and removetube from wheel.

Other tire lever options:Some tires remove easier with athinner and wider lever such the TL-2

Some tire and rimcombinations require a verystrong steel lever, such as theTL-5

6. Remove second bead from rim,which removes tire completelyfrom rim. To fully inspect thetube and tire, it is best toremove both completely.

Inspecting the InnerTubeWhen servicing a flat tire, alwaysinspect tire and tube carefully tolocate the cause of failure. This willhelp prevent future flats from thesame cause.

1. Inflate inner tube if possible.Inflate until tube is twice itsnormal width.

2. Inspect for air leaks by holdingtube close to the sensitive skinof lips or by holding tube nearyour ear to hear leaks. Movethe tube around itscircumference. If these steps

do not work, submerge tube inwater and watch for bubbles atthe hole.

3. If you plan to repair the innertube, use a marking pen tomark hole. Make four marks,one to each side of hole. Donot mark close to hole, as themark may be sanded off.

The type of cut or hole in the tubewill help determine the cause of theflat. Common causes of tire andtube failures are:

Cut at valve core, commonlyfrom misalignment of tube inrim or riding with low pressure.

Be sure tube is mountedstraight in rim and checkpressure before rides.

Leaky valve core, tighten with avalve core tool. More commonwith Schrader type valves, butalso possible on some Prestavalves.

Blow causing a large shreddedhole. These are usually notrepairable. Check tire and rim aswell for damage.

Hole on inside edge of tubeindicates a problem inside therim, such as from rim stripfailure, a protruding spoke or

other sharp object inside therim.

A long cut or rip may indicate atire blow out. Typically this isnot repairable. Use care whenseating tire during installation.

A single puncture or small hole iscommonly from a thorn, wire, orsmall nail. These may berepairable. Check tire as well forthorn, etc.

Double slits are commonly froma rim pinch. The tube waspinched between rim and objectin road/trail. Increase airpressure or use wider tires.

V-shaped slits may be from nailsor glass.

Inspecting the TireIt is important to always inspect thetire as well as the inner tube. Thecause of the flat, such as a nail orpiece of glass may still beembedded in the tire or tread.Inspect both the outside of therubber tread and the inside of thecasing.

1. Inspect outside of tread forprotruding nails, pieces ofglass, thorns, or other objects.Squeeze any cut to look insidefor objects such as slivers ofglass.

2. Visually inspect inside of tirecasing for nails, glass or debris.Wipe inside of casing with arag, and then carefully feel

inside with fingers.

3. Inspect sidewall for rips, holes,or damaged rubber and casing.

4. Inspect wire or fabric tire beadfor damage.

Rim Strip and Rim

CavityThe wheel rim is made with holesbetween the rim sidewalls for spokenipples. A rim strip covers the holesor nipples. The rim strip can bemade out of different materialssuch as cloth, rubber, orpolyurethane plastic. The stripprotects the inner tube from sharpedges in the base of the rim andfrom spoke ends and nipples thatmight puncture the tube.

Inspect inside the rim cavity,looking at the rim strip and for anysharp corners or protruding spokes.

The rim strip should be wideenough to cover the bottom of therim, but not so wide it interferes

with the seating of the tire bead.Inspect the rim strip wheneverchanging a tire or inner tube. Lookfor tares and rips, and make surerim strip is centered over the nippleholes. In the image below, the rimholes are exposed, which maycause a flat tire.

Valve TypesThere are two common types ofvalve stems on bicycles, theschrader ("American" type) and thepresta ("French" type). Theschrader or American-type valve is

common on cars and motorcycles. Itis also found on many bicycles. Thevalve stem is approximately 8mm(5/16?) in diameter and has aninternal spring plunger to assist inshutting the valve. To deflate theschrader valve tube, it is necessaryto stick a small hex wrench or otherobject into the valve in order topress on the stem and release theair. Upon release of the stem, thestem spring shuts. Schradercompatible pump fittings press onthe internal stem with a plunger,allowing the tube to be filled.

The schrader valve core can beremoved if necessary. This is rarelyrequired, but a valve can becomestuck and cause a slow leak. Aloose core can also be the source ofa slow leak. A special tool willremove and or tighten the core.

The presta or French-type valve iscommon on mid and higher pricedroad bikes and on higher pricedMTB bikes. Presta stems arenominally 6mm (1/4?) diameter,thinner than Schrader valves. At thetop of the stem is a small locknut,

which must be unthreaded beforeair can enter the tube. To deflatethe inner tube, unthread thelocknut. Depress the valve stem todeflate. To inflate the tube,unthread the locknut and tap thevalve to insure it is not stuck.

Presta valve tubes come withdifferent length valves. The longer

valve stems are needed for thedeeper aerodynamic rims.

The rim valve hole should matchthe valve of the tube. It is possibleto use the smaller presta valve in arim intended for the larger Schraderby using an adapter sleeve.

Repairing an Inner TubeSimply replacing the punctured

inner tube with a new tube isalways the safest and most reliableprocedure. However, it is possiblein some cases to repair a small holein an inner tube. If the hole is quitelarge, it may not be possible torepair. When in doubt replace thetube.

The GP-2 Super Patch Kit uses pre-glue patches. There is no tube ofglue to leak or dry up. The VP-1uses a vulcanizing fluid to bond thepatch to the inner tube.

Installing Tire and Tubeon Wheel

1. Note directional arrows of tire

manufacturer, if any.Directional arrows printed onthe sidewalls indicate rotationof wheel. Not all tires havedirection orientation.

2. Inflate tube enough for tube tojust hold its shape.

3. Install tube inside tire. Installwith tube valve adjacent to airpressure recommendationswritten on tire sidewall.

4. Lower tire and valve into rimvalve hole and align valve so itis pointing straight toward hub.A crooked valve can lead to aflat tire later.

5. Install one bead at a time.Work tire bead onto rim withhands. If tire bead will not seatusing hand, use tire lever as alast resort. Use caution whenusing tire levers to avoidpinching inner tube. Engagetire lever using sameorientation as removing bead.

6. Work tube over rim sidewall

and into rim cavity.

7. Install second bead onto rim.Use care if using a tire lever.

8. Inspect both sides of tire forbead seating and for any signof the inner tube sticking out.Re-install if necessary.

9. Inflate to low pressure andinspect bead again on bothsides. Look for small moldingline above bead. This lineshould run consistently aboverim.

10. Inflate to full pressure andcheck with pressure gauge. Itmay be necessary to pressdownward above the valve inorder to engage the pumphead. For fully threaded valveshafts, re-install the lockingnut, if any. Do not use wrenchor pliers to tighten nut. Tightenfinger tight.

Installing Wheel on BikeThe wheels must be properlymounted to the bicycle frame.Misalignment can result in problemswith shifting and bike handling. Ifthe wheel is not securely mountedin the dropouts, it may come outwhen the bike is ridden, possiblycausing injury to the rider.

Quick release wheels use a hollowhub axle fitted with a shaft, a leverthat operates a cam mechanism,and an adjusting nut. The cam putstension on the shaft and pulls boththe cam and the adjusting nut tightagainst the dropouts. This tension

is what holds the wheel securely tothe frame. The adjusting nutdetermines the amount of tensionon the quick release lever and cam.Lubricate the cam mechanism if itappears sticky or dry.

The quick release is fitted with twoconical shaped springs. The smallend of the spring faces the axle,and the large end faces outward.These springs make the wheeleasier to install. If one or bothsprings become twisted or damagedthey may be removed. The springsserve no purpose once the wheel istight on the bike.

Disc Brake NoteBicycles using disc brakes at thehub need special attention toskewer use. Rim brake systems(Dual Pivot, Linear Pull, Cantilever,Sidepull, etc.) tend not to applysignificant pressure on the axle.Disc brake systems are mounted onthe fork and apply a load on therotor, which is attached to the hub.There is an outward load on the

hub axle that tends to push the axleout of the dropout.

It is especially critical theskewer be properly and fullysecure on disc brake systems.

Non-quick release hubs use axlenuts outside the dropouts. The axlenut will have a washer built into the

nut, or a separate washer. If thewasher has teeth or knurling, theseface the dropout to help secure thewheel. Lubricate the axle threadswhile the wheel is off the bike.

It is often easiest to install the frontwheel when the bike is standing onthe ground. The quick releaseskewer must be fully engaged onthe dropout surfaces. By placing thebike on the ground, the axle will befully up in the dropouts.

1. Check that the quick releaseskewer lever is in openposition. Check that brakequick release mechanism isopen.

2. Install front wheel betweendropouts with skewer on leftside (from rider"™s point ofview). Pull wheel fully up intodropouts. For non-quick releasewheels with axle nuts, washersgo to outside of dropouts.

3. Rear wheels, pull back on rearderailleur to open chain. Placesmallest cog between upperand lower sections of chain.Guide wheel between brakepads and engage smallest cogon chain.

4. Determine final closing positionof hub quick release lever.Rotate front lever and

adjusting nut so the lever willend up just in front of fork.Position the rear lever so it fallsbetween the chain stay andseat stays. Reposition the leveras necessary if it will not fullyclose.

5. Adjust closing tension of quickrelease skewer. For mostskewers, hold lever parallel tothe hub axle, which is half way

through its swing from fullyopen to fully closed. Tightenadjusting nut snug againstdropout. Check results bymoving lever back and forththrough its swing. Lever shouldmeet resistance to closing halfway through its swing. Closelever fully.

6. For non-quick release wheels,tighten axle nuts fully.

7. Close brake quick-releasemechanism. View wheelcentering in fork. Wheel shouldbe centered between forkblades. To adjust wheelcentering, open skewer, move

wheel either left or right untilwheel appears centered, thenclose skewer. For non-quickrelease wheels, loosen axlenuts and center wheel, thentighten nuts fully.

8. Inspect brake pad alignmentand centering by closing andopening pads with brake lever.If brake pads are not centeredto wheel, see Chapter 6, BrakeSystems. If wheel fails toadequately center in frame,either the frame or wheel maybe miss aligned.

9. Spin wheel and double checkpad alignment to rim. Be sure

pads do not strike tire.

10. Orient skewer so lever will endup between the seat stay andchain stay, unless this preventslever from fully closing.

11. Close brake quick release orattach MTB brake release wire.

12. View centering of wheelbetween chain stays and seatstays. Also sight rim centeringto brake pads. Open skewer orloosen axle nuts and adjust asnecessary to center wheel inframe. If brake pads are notadequately centered to wheelre-adjust brakes. If further

attempts to align the wheel failto adequately center it inframe, either the frame orwheel may be miss aligned.Seek a professional mechanicfor help.

Note: So called "open cam"skewers may require more tensionfrom the skewer. These skewerlevers have the cam mechanismexposed, and should be lubricatedoften. Always check with skewermanufacturer for specificprocedures.

Axle NutsWheels may also be held on with anut. The rear dropouts may alsohave a derailleur hanger that boltsto the dropout. There should be a

bolt and nut that holds the hangerto the frame. The wheel installsover hanger bracket. The axleshould extend to the back of thisbracket. However, the left side axlewill appear not to sit at the back ofthe dropout. This is because theright side is displaced forward bythe hanger bracket. Center thewheel and fully secure nuts.

Front axles on some bike mayinclude a tabbed washer. There willbe a hole in the fork for the washertab.

Miscellaneous

Bike Washing andCleaningUseful Tools andSuppliesThis article will discuss bicyclewashing. Cleaning the bicyclemakes it look great, last longer, andimproves performance. For moredetail on cleaning the chainspecifically see Chain Cleaning.Washing a bike is a messy job.Begin by changing to clothes that fitthe job, and putting on an apronsuch as the SA-1 or SA-3. Next, finda work area that is appropriate.Gather together all the materials for

cleaning. See list above.

Gather supplies before being thework.

Fill the buckets with hot water. Justlike when washing dishes, warmwater cleans better. Use abiodegradable dishwashing liquid or

similar soap, and mix it in one ofthe buckets.

Add soap to water and mix.

If the bike is to be clamped, scrubinside the jaws holding the bike.Also wash area you will beclamping. The jaws will not scratch,

but if there is dirt between the jawand the paint, it may mar the finish.

Begin by cleaning the dirtiest itemsfirst, which is typically the chain anddrive train. Use a chain cleaner suchas the Park Tool CM-5 CycloneChain Scrubber.

Use the CM-5 to clean the chain.

The PRS-20 and PRS-21 RepairStands offer an option for holdingthe chain. Remove the rear wheeland reverse the frame on the stand.The axle will hold the chain forcleaning.

PRS-21 or PRS-20 holds the chainfor cleaning.

Use the GSC-1 brush to clean thederailleur pulley wheel, derailleurcage, and chainrings. Use solvent,but do not drip solvent into hub orbottom bracket bearings.

Clean greasy items with brush andsolvent.

Clean all chainrings with GSC-1.

After scrubbing the chain with theCM-5, empty the CM-5 and fill itwith soapy water. Using twodifferent types of solvents, adegreaser and a soap, is veryeffective in cleaning the chain andremoving grit.

Use soapy water to scrub chainafter using a solvent.

Wrap a rag or sponge around thechain while you spin it.

Rinse the chain with water.

If the wheels and rear gears areespecially dirty, it is best to pullthem from the bike. Scrape outpacked in grass, dirt, and grimefrom between the gears with theGSC-1.

Clean between the teeth byscrapping with a "gear comb."

Lean the wheel so the cogs arefacing the ground to minimizesolvent dripping into bearing as youscrub the cogs with solvent.

With the wheel either in or out ofthe bike, use the pointed brush toclean the hub between the flangesand outside flanges. .

Use the sponge brush to getbetween spoke nipples of the rim.

Clean the frame and the bikecomponents. Use the sponge withsoapy water to clean the tubing.Use the tapered detail brush toclean hard to reach places such asbehind the bottom bracket,derailleur and even under the

saddle.

Don'tt be shy with the sponge andsoapy water.

Use brush to clean all components.

Bottle brush cleans the hard-to-getto places.

Use the tire and frame tubecleaning brush for large tubes andtires.

If you are using a hose, use onlylow pressure with a wide spray. Letthe water drip down from above. Awater bottle may also be used forrinsing. NOTE: Mark the water

bottle as unusable, as it maybecome contaminated with soap.

Rinse bike from top down.

Allow the bike to dry after rinsing.Use compressed air if available, butdo not blast bearings directly. Use alight lubricant such as CL-1 on thechain, pulley wheels, cables, and

pivots points. After the bike iswashed, take the time to rinse offthe BCB-4 brushes and clean therepair stand.

Common Tools

AWS-1Three Way Hex Wrench

BT-2Fourth Hand Cable Stretcher

Digital Caliper

Hex Wrench Set

CN-10 Cable Cutter