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 InspectionEngine Vacuum Synchronization Inspection
NOTE
These procedures are explained on the assumption that
the intake and exhaust systems of the engine are in
good condition.
Situate the motorcycle so that it is vertical.
Remove:
Fuel Tank (see Fuel Tank Removal in the Fuel System
(DFI) chapter)
Air Cleaner Housing (see Air Cleaner ...
Fuel Hose Inspection (fuel leak, damage, installation condition)
If the motorcycle is not properly handled, the high pressure
inside the fuel line can cause fuel to leak [A] or the
hose to burst. Remove the fuel tank (see Fuel Tank Removal
in the Fuel System (DFI) chapter) and check the
fuel hoses.
Replace the fuel hose if any fraying, cracks [B] or ...
Water Pump Impeller Disassembly/Assembly
Remove the water pump impeller (see Oil Pump Removal
in the Engine Lubrication System chapter).
The sealing seat and rubber seal may be removed easily
by hand.
Apply coolant around the surfaces of the rubber seal and
sealing seat.
Install the rubber seal [A] and sealing seat [B] into ...