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:

    Introduction
    WARNINGDisc brake components rarely require disassembly. Therefore, always follow these preventive measures: Never disassemble brake components unless absolutely necessary. If any connection on the hydraulic brake system is disconnected, the entire brake sy ...

    Adjusting the engine idling speed
    NOTE: Prior to adjusting the engine idling speed, the air filter element should be clean, and the engine should have adequate compression. 1. Start the engine and let it warm up for several minutes. 2. Remove: Rider seat Refer to "GENERAL CHASSIS" on page 4-1. 3. Lift the fuel tank. ...

    Measuring the compression pressure
    NOTE: Insufficient compression pressure will result in a loss of performance. 1. Measure: Valve clearance Out of specification →Adjust. Refer to "ADJUSTING THE VALVE CLEARANCE" on page 3-3. 2. Start the engine, warm it up for several minutes, and then turn it off. 3. Remove: ...

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