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 DiscExternal Shift Mechanism Removal
Remove:
Shift Lever (see Shift Pedal Removal)
Oil Pump Drive Gear (see Oil Pump Drive Gear Removal/
Installation in the Engine Lubrication System
chapter)
Circlip [A]
Washer [B]
Special Tool - Outside Circlip Pliers: 57001-144
Remove:
Shift Shaft Assembly [A]
Washer [B] ...
Subthrottle Valve Actuator Resistance Inspection
Turn the ignition switch to OFF.
Disconnect the subthrottle valve actuator connector [A].
Connect a digital meter to the subthrottle valve actuator
connector [A].
Measure the subthrottle valve actuator resistance.
Subthrottle Valve Actuator Resistance
Connections: Y/BK lead [1 ...
How Do I Get Warranty Service?
If there is a problem with your vehicle within the limited warranty period,
you will
need to schedule a service appointment and provide any maintenance records to
an authorized Kawasaki dealer for inspection and diagnosis. You can go to any
Kawasaki dealer for warranty repairs. Your Kawasaki de ...