A common cause of battery failure is sulfation.
Sulfation occurs when the battery is left in a discharged condition for an extended time. Sulfate is a normal by product of the chemical reactions within a battery. But when continuous discharge allows the sulfate to crystallize in the cells, the battery plates become permanently damaged and will not hold a charge. Battery failure due to sulfation is not warrantable.
Battery
Battery MaintenanceWiring Diagram (Other than US, CA and CAL with KIBS Models)
ZX1000KC
ZX1000KD
...
Starter Relay Inspection
Remove the front seat (see Front Seat Removal in the
Frame chapter).
Remove the battery negative (–) cable from the battery
negative (–) terminal (see Battery Removal).
Take the starter relay [A] off the rear fender.
Remove the cover [B].
Remove:
Starter Motor Cable [A] ...
Fuel Tank and Cap Inspection
Visually inspect the gasket [A] on the tank cap for any
damage.
Replace the gasket if it is damaged.
Check to see if the water drain pipe [B] and fuel breather
pipe [C] in the tank are not clogged. Check the tank cap
breather also.
If they are clogged, remove the tank and drain it ...