NOTICE
Never drop the air switching valve especially on a hard surface. Such a shock to the air switching valve can damaged it.

Air Suction Valve Inspection
Air Switching Valve InstallationPiston Ring End Gap Inspection
Place the piston ring [A] inside the cylinder (upper
crankcase), using the piston to locate the ring squarely
in place. Set it close to the bottom of the cylinder, where
cylinder wear is low.
Measure the gap [B] between the ends of the ring with a
thickness gauge.
Piston Ring End Gap ...
Coolant Change
WARNINGCoolant can be extremely hot and cause
severe
burns, is toxic and very slippery. Do not remove
the radiator cap or attempt to change the coolant
when the engine is hot; allow it cool completely.
Immediately wipe any spilled coolant from tires,
frame, engine or othe ...
Tachometer
The tachometer shows the engine
speed in revolutions per minute (r/min,
rpm).
On the right side of the tachometer
face is a portion called the “red zone”.
Engine r/min (rpm) in the red zone is
above maximum recommended engine
speed and is also above the range for
good performance.
...