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 InspectionTransmission Assy Removal
Remove:
Engine Sprocket (see Engine Sprocket Removal in the
Final Drive chapter)
Gear Position Switch (see Gear Position Switch Removal
in the Electrical System chapter)
Collar [A]
O-ring [B]
Remove:
Clutch (see Clutch Removal in the Clutch chapter)
Shift Shaft Assembly ...
Piston Removal
Remove:
Crankshaft (see Crankshaft Removal)
Remove the piston together with the connecting rod to the
cylinder head side.
NOTICE
Discard the connecting rod bolts and nuts. To prevent
damage to the crankpin surfaces, do not allow
the connecting rod bolts to bump against the
crankpins. ...
Battery Maintenance
It is the owner’s responsibility to keep
the battery fully charged. Failure to do
so can lead to battery failure and leave
you stranded.
If you are riding your vehicle infrequently,
inspect the battery voltage
weekly using a voltmeter. If it drops
below 12.8 volts, the battery should be
...