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INSP
ADJ
IDLE SPEED ADJUSTMENT/
VALVE CLEARANCE ADJUSTMENT
IDLE SPEED ADJUSTMENT
1. Start the engine and thoroughly warm it
up.
2. Attach:
● Inductive tachometer
To spark plug lead.
3. Adjust:
● Idle speed
VALVE CLEARANCE ADJUSTMENT
OTE:
● The valve clearance should be adjusted
when the engine is cool to the touch.
● The piston must be at Top Dead Center
(T.D.C.) on compression stroke to check or
adjust the valve clearance.
1. Remove:
● Air scoop (right) 1
● Air filter case 2
2. Remove:
● Spark plug
● Tappet cover (intake side) 1
● Tappet cover (exhaust side) 2
Adjustment steps:
● Adjust the pilot screw.
Refer to “PILOT AIR SCREW ADJUST-
MENT” section.
● Turn the throttle stop screw 1 until the
engine runs at the lowest possible speed.
To increase idle speed →
Turn the throttle stop screw 1 in a.
To decrease idle speed →
Turn the throttle stop screw 1 out b.
Inductive tachometer:
YU-8036-B/90890-03113
Engine idling speed:
1,400 ~ 1,600 r/min
3. Remove:
● Timing plug 1
● Crankshaft end cover 2
● O-rings
