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 InspectionMain Throttle Sensor Output Voltage Inspection
Measure the output voltage at the main throttle sensor in
the same way as input voltage inspection, note the following.
Disconnect the main throttle sensor connector and connect
the setting adapter [A] between these connectors.
Special Tool - Throttle Sensor Setting Adapter: 57001
-15 ...
Radiator Hose and Pipe Inspection (coolant leak, damage, installation
condition)
The high pressure inside the radiator hose can cause
coolant to leak [A] or the hose to burst if the line is not
properly maintained.
Visually inspect the hoses for signs of deterioration.
Squeeze the hoses. A hose should not be hard and
brittle, nor should it be soft or swollen.
Repl ...
Exhaust Butterfly Valve Actuator Inspection
NOTE
Be sure the battery is fully charged
Remove the front seat (see Front Seat Removal in the
Frame chapter).
Turn the ignition switch to ON.
In the left side view of the motorcycle, check to see
the pulley [A] clockwise [B] and counterclockwise [C]
smoothly.
The pulley turns ...