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 camshaft
    1. Check: Camshaft lobes Blue discoloration/pitting/scratches  Replace the camshaft. 2. Measure: Camshaft lobe dimensions "a" and "b" Out of specification Replace the camshaft. 3. Check: Camshaft oil passage Obstruction Blow out with compressed air. ...

    Installing the steering head
    1. Lubricate: Upper bearing Lower bearing Bearing races 2. Install: Lower ring nut Rubber washer Upper ring nut Lock washer Refer to "CHECKING AND ADJUSTING THE STEERING HEAD" on page 3-22. 3. Install: Upper bracket Steering stem nut NOTE: Temporarily tighten t ...

    Replacing an auxiliary light bulb
    This model is equipped with two auxiliary lights. If an auxiliary light bulb burns out, replace it as follows. Remove the socket (together with the bulb) by pulling it out. Auxiliary light bulb Remove the burnt out bulb by pulling it out. Insert a new bulb into t ...

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