With the marked surface of the smaller
chainring facing away from the crank arm, set
the chainring so that the projection on the
inside is aligned with the crank arm.
Tightening torque:
< FC-CX70 >
12 - 16 N·m {106 - 139 in. lbs.}
< FC-CX50 >
12 - 14 N·m {106 - 122 in. lbs.}
Installation of the chainrings
•Smoothshiftingwillnotbepossibleifthechainringsareincorrectly
installed, so be sure to install the chainrings in the correct positions.
With the marked surface of
the larger chainring facing
out, set the larger chainring
so that the chain drop
prevention pin is lined up
with the crank arm position.
Crank arm
Outer side
Chain drop prevention pin
Installation of the front chainwheel
Follow the procedure in the figure.
1. 2. Use the TL-FC32/33/36 special tool to install the right
adapter (counterclockwise thread), the inner cover and
the left adapter (clockwise thread).
Tightening torque: 35 - 50 N·m {305 - 435 in. lbs.}
3. Insert the right crank unit.
4. Set section A of the left crank into the axle of the right
crank unit where the groove is wide.
5. Use the TL-FC16/18 to tighten the cap.
Tightening torque: 0.7 - 1.5 N·m {6 - 13 in. lbs.}
6. Push in the stopper plate and check that the plate pin is
securely in place, and then tighten the bolt of the left
crank arm. (5 mm Allen key)
Note : Each of the bolts should be evenly and equally
tightened to 12 - 14 N·m {106 - 122 in. lbs.}.
Crank arm
Projection
Mark
Inner side
SI-1MR0A-001-00
FC-CX70 / FC-CX50
Front chainwheel
Te c h n i c a l S e r v i c e I n s t r u c t i o n s SI-1MR0A-001
68 mm (1.37 x 24 T.P.I.)
70 mm (M36 x 24 T.P.I.)
SM-BB6700 SM-BB4600
110 mm
46 G – 36 G
CN-7901 / 6701
43.5 mm
B.C. 9/16" x 20 T.P.I. (English thread)
Bottom bracket shell width
(Thread dimensions)
Model number FC-CX70
Specifications
Pedal threads
Applicable chain
Chain line
Bottom bracket
Chainwheel tooth combination
Bolt circle diameter
CN-5701 / 4601
FC-CX50
General Safety Information
WARNING
“Maintenance interval depends on the usage and riding circumstances. Clean
regularly the chain with an appropriate chaincleaner. Never use alkali based or
acid based solvents such as rust cleaners. If those solvent be used chain
might break and cause serious injury.”
•Becarefulnottoletthecuffsofyourclothesgetcaughtinthechainwhileriding,otherwiseyoumay
fall off the bicycle.
•Checkthatthetensionofthechainiscorrectandthatthechainisnotdamaged.Ifthetensionistoo
weak or the chain is damaged, the chain should be replaced. If this is not done, the chain may break
and you may fall off the bicycle.
•Thetwoleftcrankarmmountingboltsshouldbetightenedalternatelyinstagesratherthaneachbolt
being fully tightened all at once. Use a torque wrench to check that the final tightening torques are
within the range of 12 - 14 N·m. Furthermore, after riding approximately 100 km (60 miles), use a
torque wrench to re-check the tightening torques. It is also important to periodically check the
tightening torques. If the tightening torques are too weak or if the mounting bolts are not tightened
alternately in stages, the left crank arm may come off and the bicycle may fall over, and serious injury
may occur as a result.
•Checkthattherearenocracksinthecrankarmsbeforeridingthebicycle.Ifthereareanycracks,the
crank arm may break and you may fall off the bicycle.
•Iftheinnercoverisnotinstalledcorrectly,theaxlemayrustandbecomedamaged,andthebicycle
may fall over and serious injury may occur as a result.
•Obtain and read the service instructions carefully prior to installing the parts. Loose, worn or
damaged parts may cause the bicycle to fall over and serious injury may occur as a result. We
strongly recommend only using genuine Shimano replacement parts.
•Obtain and read the service instructions carefully prior to installing the parts. If adjustments are
not carried out correctly, the chain may come off and this may cause you to fall off the bicycle which
could result in serious injury.
•ReadtheseTechnicalServiceInstructionscarefully,andkeeptheminasafeplaceforlaterreference.
•Ifthechainisonthesmallestorintermediatechainring,thereisthedangerofinjuryfromthetipsof
the teeth on the largest chainring.
Note
•Makesurethatthechainringcombinationmatchesthefrontchainwheeltoothconfigurationinthe
Product specifications table. If other combinations are used, the distance between the chainrings will
be incorrect and the chain might slip off and get caught in between them.
•Whenthechainisinthepositionshownintheillustration,thechainmay
contact the front chainrings or front derailleur and generate noise. If the noise is
a problem, shift the chain onto the next-larger rear sprocket or the one after.
•Ifthebottombracketshellisnotparallel,gearshiftingperformancewilldrop.
•
Before riding the bicycle, check that there is no play or looseness in the connection.
Also, be sure to retighten the crank arms and pedals at periodic intervals.
•Ifasqueakingnoiseisheardcomingfromthebottombracketaxleandtheleft
crank arm connector, apply grease to the connector and then tighten it to the specified torque.
•Useaneutraldetergenttocleanthecrankarmandthebottombracket.Usingalkalineoracidic
detergents may cause discoloration.
•Ifyoufeelanyloosenessinthebearings,thebottombracketshouldbereplaced.
•Inaddition,ifpedalingperformancedoesnotfeelnormal,checkthisoncemore.
•Donotwashthebottombracketwithhigh-pressurejetsofwater.
•Wheninstallingtheleftandrightadapters,besuretoinstalltheinnercovertoo,otherwisethe
waterproofing performance will drop.
•Applygreasetotheleftandrightadaptersbeforeinstallingthem.
•Toensurethebestperformance,besuretouseonlythespecifiedtypeofchain.Thewidetypeof
chain cannot be used.
•Ifthechainkeepscomingoffthechainringsduringuse,replacethechainringsandthechain.
•Youshouldperiodicallywashthechainringsinaneutraldetergentandthenlubricatethemagain.In
addition, cleaning the chain with neutral detergent and lubricating it can be an effective way of
extending the useful life of the chainrings and the chain.
•Thecuffsofyourclothingmaygetdirtyfromthechainwhileriding.
•Wheninstallingthepedals,applyasmallamountofgreasetothethreadstopreventthepedalsfrom
sticking. Use a torque wrench to securely tighten the pedals. Tightening torque: 35 - 55 N·m {305 - 479
in. lbs.}. The right-hand crank arm has a right-hand thread, and the left-hand crank arm has a left-hand
thread.
•Partsarenotguaranteedagainstnaturalwearordeteriorationresultingfromnormaluse.
•FormaximumperformancewehighlyrecommendShimanolubricantsandmaintenanceproducts.
•Foranyquestionsregardingmethodsofinstallation,adjustment,maintenanceoroperation,please
contact a professional bicycle dealer.
CAUTION
Front
chainrings
Rear
sprockets
