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 InspectionWindshield
Windshield Removal
Remove:
Bolts [A] and Washers
Windshield [B]
Windshield Installation
Be sure to install the wellnuts [A] and the washers.
Tighten:
Torque - Windshield Mounting Bolts: 1.2 N·m (0.12 kgf·m,
11 in·lb)
...
Brake Line Bleeding
The brake fluid has a very low compression coefficient so
that almost all the movement of the brake lever or pedal
is transmitted directly to the caliper for braking action. Air,
however, is easily compressed. When air enters the brake
lines, brake lever or pedal movement will be partially used
...
Tail/Brake Light (LED) Removal/Installation
Remove:
Upper Seat Cover (see Seat Cover Removal in the
Frame chapter)
Disconnect the tail/brake light connector [A].
Remove:
Tail/Brake Light Mounting Screws [A]
Bolts [B] and Brackets [C]
Bolt [D]
Remove the tail/brake light [A].
Bring down the rear fender rea ...