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 DiscCompression Damping Force Adjuster and Rebound
Damping Force Adjuster Adjustment
The compression damping force adjuster
and the rebound damping force
adjuster are located on top of each front
fork leg.
Turn the adjuster clockwise with a
screwdriver to increase damping
force.
Turn the adjuster counterclockwise
to decrease damping force.
NOTICE
Do not force to t ...
Brake Fluid Leak (Brake Hose and Pipe) Inspection
For KIBS equipped models, remove the fuel tank (see
Fuel Tank Removal in the Fuel System (DFI) chapter).
Apply the brake lever or pedal and inspect the brake fluid
leak from the brake hoses [A], pipes (KIBS equipped models)
[B] and fittings [C].
If the brake fluid leaked from any posit ...
Radiator and Cooling Fan
Check the radiator fins for obstruction
by insects or mud. Clean off
any obstructions with a stream of
low-pressure water.
WARNINGThe cooling fan spins at high
speed and can cause serious
injuries. Keep your hands and
clothing away from the cooling
fan blades at all times.
...