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 InspectionRear Shock Absorber Inspection
Press down on the seat several times
to inspect the stroke.
Visually inspect the rear shock absorber
for oil leaks.
If there is any doubt about the rear
shock absorber, it should be inspected
by an authorized Kawasaki
dealer.
A. Rear Shock Absorber
Spring Preload Adjustment
...
Throttle Body Assy Installation
Apply a thin coat of grease to the throttle cable lower ends.
Fit the accelerator cable end [A] and the decelerator cable
end [B] into the throttle pulley.
Install the clamp [C] securely.
Install the throttle body assy holder clamp bolt heads [A]
outside as shown in the figure.
...
Drive Chain Slack Inspection
Refer to the Drive Chain Slack Inspection in the Periodic
Maintenance chapter.
Drive Chain Slack Adjustment
Refer to the Drive Chain Slack Adjustment in the Periodic
Maintenance chapter.
Wheel Alignment Inspection/Adjustment
Refer to the Wheel Alignment Inspection in the Periodic
Maintenance ...