Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionExploded View
11. ZX1000JD/KD
AD: Apply adhesive.
AL: Tighten the two clamp bolts alternately two times to ensure even tightening
torque.
G: Apply grease.
L: Apply a non-permanent locking agent.
Specifications
...
Coupling Bearing Removal
Remove:
Coupling
Grease Seal
Circlip [A]
Special Tool - Inside Circlip Pliers: 57001-143
Remove the bearing [A] by tapping from the wheel side.
Special Tool - Bearing Driver Set [B]: 57001-1129
...
Maintenance and adjustment
The maintenance and adjustments outlined in this chapter must be carried
out in
accordance with the Periodic Maintenance Chart to keep the motorcycle in good
running condition. The initial maintenance is vitally important and must not be
neglected.
With a basic knowledge of mechanics and the ...