Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionRelease Shaft Installation
Apply grease to the oil seal lips on the upper ridge of the
clutch cover.
Apply engine oil to the needle bearings in the hole of the
clutch cover.
Applymolybdenum disulfide grease to the pusher-holding
portion [A] on the release shaft.
Install the washer [B] and spring [C].
...
Exhaust System Identification
Exhaust Pipe Mark Position [A]
Premuffler Chamber Mark Position [A]
Muffler Body Mark Position [A]
Premuffler Chamber [A] with Hole [B] for Oxygen Sensor [C]
Honeycomb Type Catalyst Position [A]
Specifications
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Tire Wear, Damage
As the tire tread wears down, the tire
becomes more susceptible to puncture
and failure. An accepted estimate is
that 90% of all tire failures occur during
the last 10% of tread life (90% worn).
So it is false economy and unsafe to
use the tires until they are bald
In accordance with the ...