Yamaha YZF-R125 Service Manual: Checking the transmission
1. Measure:
- Main axle runout
(with a centering device and dial gauge "1")
Out of specification
Replace
the main axle.
2. Measure:
- Drive axle runout
(with a centering device and dial gauge "1")
Out of specification
Replace
the drive axle.
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).
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 radiator
1. Check:
Radiator fins
obstruction clean.
Apply compressed air to the rear of the radiator.
Damage repair or replace.
NOTE:
Straighten any flattened fins with a thin, flat-head
screwdriver.
2. Check:
Radiator hoses
Cracks/damage Replace.
3. Measure:
Radiator cap ...
Rear wheel
To remove the rear wheel
WARNING
To avoid injury, securely support the
vehicle so there is no danger of it
falling over.
Loosen the axle nut.
Axle nut
Drive chain slack adjusting bolt
Locknut
Brake caliper
Lift the rear wheel off the ground
according to the pr ...
Adjusting the throttle cable free play
Throttle cable free play
The throttle cable free play should measure
3.0-5.0 mm (0.12-0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if necessary,
adjust it as follows.
TIP
The engine idling speed must be correctly
adjusted before checkin ...