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 InspectionExploded View
CL: Apply cable lubricant.
EO: Apply engine oil.
G: Apply grease.
HG: Apply high-temperature grease.
L: Apply a non-permanent locking agent.
M: Apply molybdenum disulfide grease.
R: Replacement Parts
S: Follow the specified tightening sequence.
Specifications
Special ...
External Shift Mechanism Inspection
Examine the shift shaft [A] for any damage.
If the shaft is bent, straighten or replace it.
If the serration [B] are damaged, replace the shaft.
If the spring [C] is damaged in any way, replace it.
If the shift mechanism arm [D] is damaged in any way,
replace the shaft.
Check the s ...
Valve Clearance
Valve and valve seat wear decreases
valve clearance, upsetting valve timing.
NOTICE
If valve clearance is left unadjusted,
wear will eventually
cause the valves to remain
partly open; which lowers performance,
burns the valves and
valve seats, and may cause serious
engine damage.
Valve cle ...