When the engine is running, the air intake valve is lifting up.
If the valve does not operate properly, check the air intake solenoid valve hoses for leak.
If there are no leaks, check the air intake solenoid valve.

Air Intake Solenoid Valve Unit TestCompression Damping Force Adjuster and Rebound
Damping Force Adjuster Adjustment
The compression damping force adjuster
and the rebound damping force
adjuster are located on top of each front
fork leg.
Turn the adjuster clockwise with a
screwdriver to increase damping
force.
Turn the adjuster counterclockwise
to decrease damping force.
NOTICE
Do not force to t ...
Wheel Alignment Inspection
Check that the notch [A] on the alignment indicator [B]
aligns with the same swingarm mark or position [C] that
the other side alignment indicator notch aligns with.
If they do not, adjust the chain slack and align the wheel
alignment (see Drive Chain Slack Adjustment).
NOTE
Wheel align ...
Camshaft Removal
Remove:
Cylinder Head Cover (see Cylinder Head Cover Removal)
Crankshaft Sensor Cover (see Crankshaft Sensor Removal
in the Electrical System chapter)
Using a wrench on the timing rotor bolt [A], turn the crankshaft
clockwise until the line [B] (TDC mark for #1,4 pistons)
on the timin ...