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:
Disassembling the rear brake caliper
1. Remove:
Brake caliper piston "1"
Brake caliper piston dust seal "2"
Brake caliper piston seal "3"
a. Blow compressed air into the brake hose joint
opening "a" to force out the piston from the
brake caliper.
WARNING
Cover the brake caliper piston with a rag.
Be careful no ...
Assembling the main axle and drive axle
1. Install:
Toothed washer "1"
Circlip "2"
NOTE:
Be sure to install the circlip so that its sharp
edge "a" is facing away from the toothed washer
and gear.
Be sure the circlip ends "b" are positioned at
the axle spline groove "c".
2. Install:
2nd pinion gear "1"
NO ...
Disassembling the front wheel
1. Remove:
Oil seal
Wheel bearings
a. Clean the surface of the front wheel hub.
b. Remove the oil seal "1" with a flat-head
screwdriver.
NOTE:
To prevent damaging the wheel, place a rag "2"
between the screwdriver and the wheel surface.
c. Remove the wheel bearings "3" with a ge ...