If there are notches worn into the splines, replace the sub clutch hub. Also, replace the steel plates if their teeth are damaged.

Clutch Housing Finger Inspection
Damper Cam InspectionChain Slack Adjustment
Remove the cotter pin, and loosen
the axle nut.
Loosen the left and right chain adjuster
locknuts.
A. Axle Nut
B. Cotter Pin
C. Adjuster
D. Locknut
If the chain is too loose, turn out the
left and right chain adjusters evenly.
If the chain is too tight, turn in the left
...
Transmission Shaft Assembly
Apply molybdenum disulfide oil solution to the sliding surfaces
of the gears and shafts.
Install the gears and the gear bushings [A] with their holes
[B] aligned.
Replace any circlips removed with new ones.
Install the circlips [A] so that the opening [B] of it is aligned
with ...
Shifting Gears
Close the throttle while pulling in the
clutch lever.
Shift into the next higher or lower
gear.
Open the throttle part way, while releasing
the clutch lever.
For smooth riding, each gear position
should cover the proper rate of speed
shown in the table.
WARNINGDownshifti ...