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 InspectionLoading and accessories information
WARNINGIncorrect loading, improper installation
or use of accessories,
or modification of your motorcyclemay
result in an unsafe riding
condition. Before you ride the
motorcycle, make sure it is not
overloaded and that you have
followed these instructions.
With the ...
Upper Crankcase Assembly
When installing the breather plate, replace the gasket [A]
with a new one.
Apply a non-permanent locking agent to the threads of
the bolts [A] and tighten them.
Torque - Breather Plate Bolts: 9.8 N·m (1.0 kgf·m, 87 in·lb)
Install the fitting [A] until it is bottomed ...
Subthrottle Sensor Input Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Remove the air cleaner housing (see Air Cleaner Housing
Removal in the Fuel System (DFI) chapter)
Disconnect the subthrottle sensor connector and connect
the harness adapter [A] between these connectors.
Spec ...