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 AgentRear Master Cylinder Removal
Unscrew the brake hose banjo bolt [A] and remove the
brake hose (see Brake Hose and Pipe Replacement in
the Periodic Maintenance chapter).
Remove:
Rear Master Cylinder Mounting Bolts [B]
Foot Guard [C]
Screw and Stopper [D]
Bolt [E]
Front Footpeg Bracket Bolts [F]
Cable Guide [G ...
Engine Sprocket Installation
Replace the sprocket washer and axle cotter pin.
Install the engine sprocket onto the output shaft.
Apply molybdenum disulfide oil solution to the threads
and seating surface of the engine sprocket nut.
Tighten:
Torque - Engine Sprocket Nut: 145 N·m (14.8 kgf·m, 107
ft·lb)
NOTE
...
Chain Slack Inspection
Set the motorcycle up on its side
stand.
Rotate the rear wheel to find the position
where the chain is tightest, and
measure the maximum chain slack
by pulling up and pushing down the
chain midway between the engine
sprocket and rear wheel sprocket.
A. Chain Slack
If the ...