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 rectifier/regulator
1. Check: Rectifier/regulator output voltage Out of specification → Replace the rectifier/ regulator. a. Set the engine tachometer to the spark plug lead. b. Connect the pocket tester (DC 20 V) to the rectifier/regulator coupler as shown. Positive tester probe red "1" Negat ...

Faulty lighting or signaling system
Headlight does not come on - Wrong headlight bulb - Too many electrical accessories - Hard charging - Incorrect connection - Improperly grounded circuit - Poor contacts (main or light switch) - Burnt-out headlight bulb Headlight bulb burnt out - Wrong headlight bulb - Faulty battery - Fau ...

Changing the coolant
1. Remove: Lower side cowlings Refer to "GENERAL CHASSIS" on page 4-1. 2. Remove: Radiator cap "1" WARNINGA hot radiator is under pressure. Therefore, do not remove the radiator cap when the engine is hot. Scalding hot fluid and steam may be blown out, which c ...