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 InspectionLiquid Gasket, Non-permanent Locking Agent
For applications that require Liquid Gasket or a
Non-permanent Locking Agent, clean the surfaces so
that no oil residue remains before applying liquid gasket or
non-permanent locking agent. Do not apply them excessively.
Excessive application can clog oil passages and
cause serious damage.
...
ESD Actuator Resistance Inspection
Turn the ignition switch to OFF.
Remove the electronic steering damper unit (see Steering
Damper Removal in the Steering chapter).
Connect a digitalmeter to the ESD actuator connector [A].
Measure the ESD actuator resistance.
ESD Actuator Resistance
Connections: BK lead [1] ← ...
Handlebar Installation
Apply a non-permanent locking agent to the threads of
the handlebar positioning bolts and tighten them.
Torque - Handlebar Positioning Bolts: 9.8 N·m (1.0 kgf·m,
87 in·lb)
Install the steering stem head with handlebars.
Install the washer [A] and steering stem head nut [B].
Tighten:
...