Yamaha YZF-R125 Service Manual: Faulty clutch
Clutch slips
1. Clutch
- Improperly assembled clutch
- Improperly adjusted clutch cable
- Loose or fatigued clutch spring
- Worn friction plate
- Worn clutch plate
2. Engine oil
- Incorrect oil level
- Incorrect oil viscosity (low)
- Deteriorated oil
Clutch drags
1. Clutch
- Unevenly tensioned clutch springs
- Warped pressure plate
- Bent clutch plate
- Swollen friction plate
- Bent clutch push rod
- Broken clutch boss
- Burnt primary driven gear bushing
2. Engine oil
- Incorrect oil level
- Incorrect oil viscosity (high)
- Deteriorated oil
Jumps out of gear
Shift shaft
Incorrect shift pedal position
Improperly returned stopper lever
Shift forks
Worn shift fork
Shift drum
Incorrect axial play
Worn shift drum groove
Transmission
...
Overheating
Engine
1. Clogged coolant passages
Cylinder head and piston
Heavy carbon buildup
2. Engine oil
Incorrect oil level
Incorrect oil viscosity
Inferior oil quality
Cooling system
1. ...
Other materials:
Installing the swingarm
1. Lubricate:
Bearings
Spacers
Dust covers
Pivot shaft
2. Install:
Bearings "1"
2. Swingarm
A. Left side
B. Right side
3. Install:
Swingarm adjusting collar "1"
Swingarm "2"
Pivot shaft
Pivot shaft nut "3"
a. Install, and then fully turn in the swingarm adju ...
Checking the decompression system
1. Check:
Decompression system
a. Check the decompression system with the
camshaft sprocket and the decompression
cam installed to the camshaft.
b. Check that the decompression lever "1"
moves smoothly.
c. Without operating the decompression lever,
check that the decompression cam " ...
Installing the crankshaft
1. Install:
Crankshaft "1"
NOTE:
Install the crankshaft with the crankshaft installer
pot "2", crankshaft installer bolt "3", adapter
(M12) "4" and spacer (crankshaft installer) "5".
CAUTION:To avoid scratching the crankshaft and to
ease the installation procedure, lubricate ...