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 AgentService Code Erasing
When repair has been done, warning indicator light (LED) and warning symbol
go off and service
code are not displayed.
But the service codes stored in memory of the ECU are not erased to preserve
the problem history.
In this model, the problem history can not be erased. However, the memorie ...
Brake Pad Wear Inspection
Remove the brake pads (see Front/Rear Brake Pad Removal
in the Brakes chapter).
Check the lining thickness [A] of the pads in each caliper.
If the lining thickness of either pad is less than the service
limit [B], replace both pads in the caliper as a set.
Front Brake Pad [C]
Rea ...
Cylinder (Upper Crankcase) Wear Inspection
Split the crankcase (see Crankcase Splitting).
Remove the pistons (see Piston Removal).
Assemble the cylinder (upper crankcase) [A], the cylinder
head [B] and the cylinder head gasket [C].
Tighten the cylinder head bolts (see Cylinder Head Installation
in the Engine Top End chapter).
...