Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionTightening Sequence
Generally, when installing a part with several bolts, nuts,
or screws, start them all in their holes and tighten them to
a snug fit. Then tighten them according to the specified sequence
to prevent case warpage or deformation which can
lead to malfunction. Conversely when loosening the bolts,
n ...
Wiring Diagram (US, CA and CAL with KIBS Models)
ZX1000KC
ZX1000KD
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Sidestand Removal
Raise the rear wheel off the ground with the stand [A].
Remove:
Sidestand Switch Bolt [A]
Sidestand Switch [B]
Remove:
Spring [A]
Sidestand Nut [B]
Sidestand Bolt [C]
Sidestand [D]
...