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 DiscParts Removal/Installation
WARNINGGasoline is extremely flammable and can be
explosive
under certain conditions. Turn the ignition
switch OFF. Do not smoke. Make sure the area is
well-ventilated and free from any source of flame
or sparks; this includes any appliance with a pilot
light.
NOTICE
...
Check 2-3: Intake Air Temperature Inspection
Disconnect the intake air temperature sensor connector
[A] (see Intake Air Temperature Sensor Removal in the
Self-Diagnosis System chapter).
Connect the variable rheostat [B] to the R/BK lead [C] and
BR/BK lead [D] terminals.
Turn the ignition switch to ON.
Read the temperatur ...
Compression Damping Force Adjustment
The compression damping force adjusters
for high and low speeds are located
on the gas reservoir at the left
side of the rear shock absorber.
A. High Speed Adjuster
B. Low Speed Adjuster
NOTE
Turning the high speed adjuster has
the low speed adjuster turning. Although
the low speed adju ...