If the teeth are worn as illustrated, replace the sprocket, and inspect the drive chain wear (see Drive Chain Wear Inspection in the Periodic Maintenance chapter).
Worn Tooth (Engine Sprocket) [A] Worn Tooth (Rear Sprocket) [B] Direction of Rotation [C]
NOTE
If a sprocket requires replacement, the chain is probably worn also. When replacing a sprocket, inspect the chain.

Coupling Damper Inspection
Rear Sprocket Warp InspectionSidestand Installation
Replace the sidestand nut [A] with a new one.
Apply grease to the sliding areas [B].
Tighten the sidestand bolt [C] first, and then the sidestand
nut.
Torque - Sidestand Bolt: 44 N·m (4.5 kgf·m, 32 ft·lb)
Sidestand Nut: 29 N·m (3.0 kgf·m, 21 ft·lb)
Install the spring [D] as sh ...
Radiator and Cooling Fan
Check the radiator fins for obstruction
by insects or mud. Clean off
any obstructions with a stream of
low-pressure water.
WARNINGThe cooling fan spins at high
speed and can cause serious
injuries. Keep your hands and
clothing away from the cooling
fan blades at all times.
...
ESD (Electronic Steering Damper) ECU Error (Service Code E3b, ZX1000JD/KD)
If this service code appears, check that the following parts
are correctly.
Crankshaft Sensor
Gear Position Switch
Starter Lockout Switch
Main Throttle Sensor
Rear Wheel Rotation Sensor
If these parts are normal, check the ESD ECU for its
ground and power supply (see ESD ECU Power Supply
...