Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionWiring Diagram (US, CA and CAL with KIBS Models)
ZX1000KC
ZX1000KD
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Precautions
1) No need of topping-up
No topping-up is necessary in this battery until it ends its life under
normal use. Forcibly prying
off the seal cap to add water is very dangerous. Never do that.
2) Refreshing charge.
Give refresh charge for 5 to 10 hours with charge current shown in the text
(see ...
Piston 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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