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 DiscGear Position Switch Removal
Remove:
Oil Pump (see Oil pump Removal in the Engine Lubrication
System chapter)
Engine Sprocket (see Engine Sprocket Removal in the
Final Drive chapter)
Fuel Tank (see Fuel Tank Removal in the Fuel System
(DFI) chapter)
Disconnect the connector [A].
Remove:
Screws [A]
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Replacement Parts
Replacement parts must be KAWASAKI genuine or
recommended by KAWASAKI. Gaskets, O-rings, oil seals,
grease seals, circlips, cotter pins or self-locking nuts must
be replaced with new ones whenever disassembled.
Assembly Order
In most cases assembly order is the reverse of disassembly,
howe ...
Front Seat Installation
Installation is the reverse of removal. Note the following.
Check that the dampers [A] are in place on the front seat.
Install the collars [B] as shown in the figure.
Place the seat hooks [A] under the fuel tank bracket [B].
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