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 InspectionStarter Motor Installation
NOTICE
Do not tap the starter motor shaft or body. Tapping
the shaft or body could damage the motor.
Clean the starter motor legs [A] and crankcase where the
starter motor is ground.
Replace the O-ring [A] with a new one.
Apply grease to the new O-ring.
Tighten:
Torque - Starter ...
Fuel Tank and Cap Inspection
Visually inspect the gasket [A] on the tank cap for any
damage.
Replace the gasket if it is damaged.
Check to see if the water drain pipe [B] and fuel breather
pipe [C] in the tank are not clogged. Check the tank cap
breather also.
If they are clogged, remove the tank and drain it ...
Oil Cooler Removal
Remove:
Coolant (Drain, see Coolant Change in the Periodic
Maintenance chapter)
Engine Oil (Drain, see Engine Oil Change in the Periodic
Maintenance chapter)
Lower Fairings (see Lower Fairing Removal in the Frame
chapter)
Water Hose Ends [A] (Disconnect)
Remove:
Oil Cool ...