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:

Installing the clutch
1. Install: Conical spring washer "1" NOTE: Install the conical spring washer as shown in the illustration. 2. Install: Clutch housing Thrust washer "1" NOTE: Be sure to install the thrust washer so that its sharp edge "a" is facing away from the clutch boss. 3. Instal ...

Incorrect engine idling speed
Engine 1. Cylinder and cylinder head Incorrect valve clearance Damaged valve train components 2. Air filter Clogged air filter element Fuel system 1. Throttle body Damaged or loose throttle body joint Improperly adjusted engine idling speed (idle adjusting screw) Improper ...

Faulty front fork legs
Leaking oil - Bent, damaged or rusty inner tube - Cracked or damaged outer tube - Improperly installed oil seal - Damaged oil seal lip - Incorrect oil level (high) - Loose damper rod assembly bolt - Damaged damper rod assembly bolt copper washer - Cracked or damaged front fork cap O-ring M ...