Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionPiston Wear Inspection
Measure the outside diameter [A] of each piston 5 mm
(0.20 in.) [B] up from the bottom of the piston at a right
angle to the direction of the piston pin.
If the measurement is under service limit, replace the piston.
Piston Diameter
Standard: 75.959 75.974 mm
(2.9905 2.9911 in.)
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Technical Information - Electronic Steering Damper (ESD/ZX1000JD/KD models)
1) Overview
This model has an Electronic Steering Damper (ESD)
[A]. Unlike conventional manual adjustment method of
Kawasaki, damping characteristics are adjusted by the
electronic control unit.
2) Purpose
Designed to offer increased stability at high speed without interfering with
light ...
Main Throttle Sensor Resistance Inspection
Turn the ignition switch to OFF.
Measure the main throttle sensor resistance in the same
way as input voltage inspection, note the following.
Disconnect the throttle sensor setting adapter [A] from the
connector of the main harness side.
Special Tool - Throttle Sensor Setting Adapter: 57 ...