Owner`s manual

54 TREK SERVICE INFORMATION 17 July 2013
Crankset Troubleshoong
This section describes problems that occasionally occur, and possible solutions. If these
solutions do not solve a problem, contact Customer Service.
Bearing Play In A GXP Crank Or Boom Bracket Assembly
The crank feels loose when grasped at the pedal end and rocked side-to-side.
Cause Solution
Wave washer not
compressed fully
This is usually caused by
insucient torque on the non-
drive crank arm.
In rare instances a tolerance stack
can be created by the ve crical
parts: non-drive bearing, drive
bearing, drive-side seal, boom
bracket shell, and axle length.
First, verify that the crank has been tightened to the torque
specifications (see page 38). Most issues with play in
GXP crankarms are resolved when the arms are properly
tightened.
If this does not solve the issue, add a 0.5 mm washer/spacer
(PN 294162) between the wave washer and seal
(Figure 14.39) to increase the bearing preload.
Spline of GXP crankarm is
undersized
• We have seen some variaon in
the tolerance of GXP crankarms.
• If the installaon torque is not
sucient, the crank arm will not
completely compress the shield
and bearing race.
Remove the crankarm and re-install with plenty of grease.
Verify that the crank has been tightened to the torque
specifications (see page 38).
Re-check the bearings after installation. The GXP axle
spline is tapered, so it requires that the crank be completely
tightened to seat on the axle.
Figure 14.39. SRAM bearing set
Seal
Bearing
Wave washer
Spacer