Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionFuse Box Fuse Removal
Remove the left upper inner fairing (see Upper Inner Fairing
Removal in the Frame chapter).
Unlock the hook [A] to take off the fuse box 1 [B].
Unlock the hook [C] to lift up the lid.
Pull the fuses [A] straight out of the fuse box 1 with needle
nose pliers.
Fuse Box 2
...
Damping Force Adjustment (
ZX1000JC/KC)
To adjust the damping force, turn the damping adjuster
[A] until you feel a click.
The standard adjuster setting is the 18th click from the
1st of the fully clockwise position. If the damping feels too
soft or too stiff, adjust it in accordance with the following
table.
Damping Force Adj ...
Front Fork Oil Change
Remove the front fork (see Front Fork Removal (Each
Fork Leg)).
Turn the spring preload adjuster fully counterclockwise for
removing the piston rod assy easily.
Hold the inner tube lower end in a vise.
Using the wrench [A], unscrew the top plug [B] out of the
outer tube.
Special Too ...