Yamaha YZF-R125 Service Manual: Checking the transmission

Yamaha YZF-R125 Service Manual / Engine / Transmission / Checking the transmission

1. Measure:

Main axle runout (with a centering device and dial gauge "1") Out of specification Replace
the main axle.

Checking the transmission

2. Measure:

Drive axle runout (with a centering device and dial gauge "1") Out of specification Replace
the drive axle.

Checking the transmission

3. Check:

Transmission gears Blue discoloration/pitting/wear
Replace the defective gear(s).
Transmission gear dogs Cracks/damage/rounded edges
Replace the defective gear(s).

Checking the transmission

4. Check:

Transmission gear engagement (each pinion gear to its respective wheel gear) Incorrect Reassemble the
transmission axle assemblies.

5. Check:

Transmission gear movement Rough movement Replace the
defective part(s).

Checking the shift drum assembly

1. Check: Shift drum groove Damage/scratches/wear Replace the shift drum assembly. Shift drum segment "1" Damage/wear Replace the shift drum assembly. Shift drum bearing "2" ...

Checking the clutch push rods

1. Check: Long clutch push rod Cracks/damage/wear Replace the long clutch push rod. 2. Measure: Push rod bending limit Out of specification Replace the long clutch push rod. ...

Other materials:

Checking the front brake master cylinder
1. Check: Brake master cylinder Damage/scratches/wear Replace. Brake fluid delivery passages (brake master cylinder body) Obstruction Blow out with compressed air. 2. Check: Brake master cylinder reservoir Cracks/damage Replace the brake master cylinder. Brake maste ...

Installing the drive chain
1. Lubricate: Drive chain Master link 2. Install: Drive sprocket Drive sprocket retainer bolts 3. Install: Master link O-rings Master link plate Master link clip "1" CAUTION: The closed end of the master link clip must face in the direction of drive ch ...

Checking the timing chain tensioner
1. Check: Timing chain tensioner Cracks/damage/rough movement Replace. a. Lightly press the timing chain tensioner rod into the timing chain tensioner housing by hand. NOTE: While pressing the timing chain tensioner rod, wind it clockwise with a thin screwdriver "1" until it stops. b. ...