If a master cylinder or piston shows any damage, replace them.

If a cup is worn, damaged softened (rotted), or swollen, the piston assembly should be replaced to renew the cups.
If fluid leakage is noted at the brake lever, the piston assembly should be replaced to renew the cups.
If they are damaged, replace them.
If the springs are damaged, replace them.
If the relief port becomes plugged, the brake pads will drag on the disc. Blow the ports clean with compressed air.
Front Master Cylinder [I] Rear Master Cylinder [J]

Rear Master Cylinder Installation
Brake DiscAxle Inspection
Remove the front and rear axles (see Front/Rear Wheel
Removal).
Visually inspect the front and rear axle for damages.
If the axle is damaged or bent, replace it.
Place the axle in V blocks that are 100 mm (3.94 in.) [A]
apart, and set a dial gauge [B] on the axle at a point
halfway ...
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 ...
Fuel Tank Installation
Note the above WARNING (see Fuel Tank Removal).
Run the hoses correctly (see Cable, Wire, and Hose Routing
section in the Appendix chapter).
Check that the dampers [A] are in place on the fuel tank.
If the dampers are damaged or deteriorated, replace
them.
If the fuel tank brack ...