If they appear damaged or deteriorated, replace them.

Balancer Adjustment
Torque LimiterPremuffler Chamber Removal
Remove:
Muffler Body (see Muffler Body Removal)
Right Lower Fairing (see Lower Fairing Removal in the
Frame chapter)
Front Seat (see Front Seat Removal in the Frame chapter)
Oxygen Sensor (Equipped Models) (see Oxygen Sensor
Removal (Equipped Models) in the Electrical System
chapter ...
Starter Motor Installation
NOTICE
Do not tap the starter motor shaft or body. Tapping
the shaft or body could damage the motor.
Clean the starter motor legs [A] and crankcase where the
starter motor is ground.
Replace the O-ring [A] with a new one.
Apply grease to the new O-ring.
Tighten:
Torque - Starter ...
Brake Disc Installation
Install the brake disc on the wheel so that the marked side
[A] faces out.
Front Brake Discs [B]
Rear Brake Disc [C]
Apply a non-permanent locking agent to the threads of
the brake disc mounting bolts.
Tighten:
Torque - Brake Disc Mounting Bolts: 27 N·m (2.8 kgf·m, 20
...