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 wheel
    1. Check: Front wheel axle Roll the wheel axle on a flat surface. Bends → Replace. WARNINGDo not attempt to straighten a bent wheel axle. 2. Check: Tire Front wheel Damage/wear → Replace. Refer to "CHECKING THE TIRES" on page 3-23 and "CHECKING TH ...

    Catalytic converters
    This vehicle is equipped with catalytic converters in the exhaust system. WARNING The exhaust system is hot after operation. To prevent a fire hazard or burns: Do not park the vehicle near possible fire hazards such as grass or other materials that easily burn. Park the vehic ...

    Engine oil and oil filter element
    The engine oil level should be checked before each ride. In addition, the oil must be changed and the oil filter element replaced at the intervals specified in the periodic maintenance and lubrication chart. To check the engine oil level Place the vehicle on a level surface and hol ...

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