Hardening, shrinkage, or damage of both gaskets and O-rings after disassembly can reduce sealing performance.
Remove old gaskets and clean the sealing surfaces thoroughly so that no gasket material or other material remains.
Install the new gaskets and replace the used O-rings when re-assembling.

Force
Liquid Gasket, Non-permanent Locking AgentAir Cleaner Oil Draining
A drain hose is connected to the bottom of the air cleaner
to drain water or oil accumulated in the cleaner part.
Visually check the drain hose [A] if the water or oil accumulates.
If any water or oil accumulates in the hose, remove the
plug [B] from the drain hose and drain it.
...
Wheel Bearing Damage Inspection
Raise the front wheel off the ground with the jack (see
Front Wheel Removal in the Wheels/Tires chapter).
Special Tools - Jack: 57001-1238
Jack Attachment: 57001-1608
Turn the handlebar all the way to the right or left.
Inspect the roughness of the front wheel bearing by moving
[A] ...
Meter Unit Circuit (ZX1000K Model)
1. Ignition Switch
2. Joint Connector F
3. Stop Watch Button
4. Oil Pressure Switch
5. Crankshaft Sensor
6. Water Temperature Sensor
7. Gear Position Switch
8. Intake Air Temperature Sensor
9. ESD ECU (ZX1000JD/KD)
10. ECU
11. Rear Wheel Rotation Sensor
12. Frame Ground 1
13. Engine ...