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 DiscRadiator and Radiator Fan Removal
Remove:
Upper Fairing Assembly (see Upper Fairing Assembly
Removal in the Frame chapter)
Coolant (Drain, see Coolant Change in the Periodic
Maintenance chapter)
Air Cleaner Housing (see Air Cleaner Housing Removal
in the Fuel System (DFI) chapter)
Coolant Reserve Tank (see Coolant R ...
Engine Removal
Support the rear part of the swingarm with a stand.
Squeeze the brake lever slowly and hold it with a band
[A].
WARNINGMotorcycle may fall over unexpectedly
resulting in
an accident or injury. Be sure to hold the front brake
when removing the engine.
NOTICE
Be sure ...
Exploded View
10. US, CA, CAL and AU Models
11. ZX1000JD/KD
G: Apply grease.
L: Apply a non-permanent locking agent.
R: Replacement Parts
S: Follow the specified tightening sequence.
1. US, CA and CAL Models
2. ZX1000J Model
3. ZX1000K Model
4. AU Model
5. Face the large diameter side re ...