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 oil pump
1. Check: Oil pump drive gear Oil pump driven gear Oil pump housing Oil pump housing cover Cracks/damage/wear Replace the defective part(s). 2. Measure: Inner-rotor-to-outer-rotor-tip clearance "a" Outer-rotor-to-oil-pump-housing clearance "b" - Oil-pump-housing-to-inn ...

Checking the stator coil
1. Disconnect: Stator coil coupler (from the wire harness) 2. Check: Stator coil resistance Out of specification → Replace the crankshaft position sensor/stator assembly. a. Connect the pocket tester ( × 1) to the stator coil coupler as shown. b. Measure the sta ...

Starting circuit cut-off system operation
If the engine stop switch is set to " " and the main switch is set to "ON" (both switches are closed), the starter motor can only operate if at least one of the following conditions is met: The transmission is in neutral (the neutral switch is closed). The clutch lever is pulled to the ...