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 Shaft Disassembly
Remove the transmission shafts (see Transmission Shaft
Removal).
Remove the circlips, and then disassemble the transmission
shafts.
Special Tool - Outside Circlip Pliers: 57001-144
The 5th gear [A] on the output shaft has three steel balls
assembled into it for the positive neutral fin ...
Front Fork Installation (Each Fork Leg)
Install the fork so that the top plug end [A] as shown in the
figure.
11 mm (0.43 in.) [B]
Steering Stem Head [C]
Tighten:
Torque - Front Fork Clamp Bolts (Lower): 23 N·m (2.3
kgf·m, 17 ft·lb)
NOTE
Tighten the two lower front fork clamp bolts alternately
two times to ensur ...
Hub Bearing Removal
Remove the wheels (see Front/Rear Wheel Removal),
and take out the following.
Collars
Coupling (Out of rear hub)
Grease Seals
Use the bearing remover to remove the hub bearings [A].
NOTICE
Do not lay the wheel on the ground with the disc
facing down. This can damage or warp the d ...