Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionMuffler Body Installation
Replace the muffler body gasket [A] with a new one.
Install the muffler body gasket to the premuffler chamber
[B] until it is bottomed so that the chamfer side faces premuffler
chamber.
Install the muffler body clamp [C] as shown in the figure.
Insert the projection [D] into the slot [ ...
Wiring Diagram (US, CA and CAL with KIBS Models)
ZX1000KC
ZX1000KD
...
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 ...