If they appear damaged or deteriorated, replace them.

Balancer Adjustment
Torque LimiterEngine Vacuum Synchronization Inspection
NOTE
These procedures are explained on the assumption that
the intake and exhaust systems of the engine are in
good condition.
Situate the motorcycle so that it is vertical.
Remove:
Fuel Tank (see Fuel Tank Removal in the Fuel System
(DFI) chapter)
Air Cleaner Housing (see Air Cleaner ...
Fuel Type
Use clean, fresh unleaded gasoline
with a minimum Antiknock Index of 90.
The Antiknock Index is posted on service
station pumps. The octane rating
of a gasoline is a measure of its resistance
to detonation or “knocking.” The
Antiknock Index is an average of the
Research Octane Number (R ...
Cylinder Head Warp Inspection
Clean the cylinder head.
Lay a straightedge across the lower surface of the cylinder
head at several positions.
Use a thickness gauge [A] to measure the space between
the straightedge [B] and the head.
Cylinder Head Warp
Standard: – – –
Service Limit: 0.05 mm (0.0020 in.)
...