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 DiscFuel Pump Operating Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Remove:
Fuel Tank Bolts (see Fuel Tank Removal)
Fuel Tank Bracket Bolts (see Fuel Tank Removal)
Disconnect the fuel pump lead connector and connect the
harness adapter [A] between these connectors as shown
i ...
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
...
Operational Cautions
1. Do not put two keys of any immobilizer system on the same key ring.
2. Do not submerge any key in water.
3. Do not expose any key to excessively high temperature.
4. Do not place any key close to magnet.
5. Do not place a heavy item on any key.
6. Do not grind any key or alter its ...