Shimano FC-MX71 Service Instructions

Model number

Crank arm length

Pedal threads

Applicable chain

Chain line

Applicable bottom bracket

Chainwheel tooth combination

Bolt circle diameter

One Holland, Irvine, California 92618, U.S.A. Phone: [phone]

Industrieweg 24, 8071 CT Nunspeet, The Netherlands Phone: [phone]

3-77 Oimatsu-cho, Sakai-ku, Sakai-shi, Osaka 590-8577, Japan

Technical Service Instructions SI-1MA0A-001

Front chainwheel

FC-MX71

FC-MX71 (SM-CR80-A)

104 mm

34 / 38 / 41 / 42 / 43 / 44 / 46 T

CN-7701

44 mm

B.C. 9/16" x 20T.P.I. (English thread)

165, 170, 175, 180 mm

68 mm (1.37 X 24 T.P.I.)

Installation of the front chainwheel

Follow the procedure in the figure.

1, 2 Use the special tool TL-FC32/36 to install the right

adapter (counterclockwise thread) 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.}.

General Safety Information

WARNING

• Be careful not to let the cuffs of your clothes get caught in the chain while riding, otherwise
you may fall off the bicycle.

• Check that the tension of the chain is correct and that the chain is not damaged. If the
tension is too weak or the chain is damaged, the chain should be replaced. If this is not
done, the chain may break and cause serious injury.

• The two left crank arm mounting bolts should be tightened alternately in stages rather than
each bolt 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.

• Check that there are no cracks in the crank arms before riding the bicycle. If there are any
cracks, the crank arm may break and you may fall off the bicycle.

• If the inner cover is not installed correctly, the axle may rust and become damaged, and the
bicycle 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.

• Read these Technical Service Instructions carefully, and keep them in a safe place for later
reference.

Note

• In addition, if pedaling performance does not feel normal, check this once more.

• 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.

• If a squeaking noise is heard coming from the bottom bracket axle and the left crank arm
connector, apply grease to the connector and then tighten it to the specified torque.

• Use a neutral detergent to clean the crank arm and the bottom bracket. Using alkaline or
acidic detergents may cause discoloration.

• Do not wash the bottom bracket with high-pressure jets of water.

• If you feel any looseness in the bearings, the bottom bracket should be replaced.

• You should periodically wash the chainrings in a neutral detergent and then lubricate them
again. 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.

• If the chain keeps coming off the chainrings during use, replace the chainrings and the
chain.

• The cuffs of your clothing may get dirty from the chain while riding.

• Apply grease to the left and right adapters before installing them.

• Parts are not guaranteed against natural wear or deterioration resulting from normal use.

• For maximum performance we highly recommend Shimano lubricants and maintenance
products

• For any questions regarding methods of installation, adjustment, maintenance or operation,
please contact a professional bicycle dealer.

■ Spacer installation method

(1) Check whether the width of the bottom bracket

shell is 68 mm.

(2) Next, install the adapter while referring to the

illustrations below.

(2.5 mm)

68 mm

68mm

6

2

1

3

Wide groove area

TL-FC16

Stopper plate

Plate pin

Push up

5

4

(A)

TL-FC32

Inner cover

Note :

Set the stopper plate in the right
direction as shown in illustration.

Bottom bracket shell

Apply grease to the left and right
adapters before installing them.

SI-1MA0A-001-00

Note:

• When installing, make sure that the chainring is facing the
correct way. The surface with the Shimano logo should face
toward the outside.

• Check that the nuts are securely fitted into the counterbores on
the inside of the chainring as shown in the illustration, and then
tighten the bolts.

Specifications

Install the chainring to the right­side crank arm as shown in the
illustration.

Installation of the chainring (SM-CR80-A)

Tightening torque :

14 - 16 N·m {122 - 139 in. lbs.}

SM-CR80-A

Counterbore

Nut

Inside Outside Outside

Bolt

Nut

SM-BB70-S

Bottom bracket shell width
(Thread dimensions)

Inside

* Service Instructions in further languages are available at : http://techdocs.shimano.com

Please note: specifications are subject to change for improvement without notice.(English)
© Jun. 2010 by Shimano Inc. XBC SZK Pr inted in Japan.