KYMCO Venox 250, Service Manual

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2
. INSPECTION/ADJUSTMENT
2-13
VENOX250/250i
VALVE CLEARANCE
Remove the four cylinder head cover bolts and the
cylinder head cover.
Front cylinder :
Rotate the generator flywheel to bring the camshaft to
the top dead center on the compression stroke and
align the “T1” mark on the flywheel with the mark on
the left crankcase cover.
Rear cylinder :
Rotate the generator flywheel for 270º
counterclockwise to bring the camshaft to the top
dead center on the compression stroke and align the
“T2” mark on the flywheel with the mark on the left
crankcase cover.
Inspect and adjust the valve clearance.
Valve Clearance : IN : 0.1mm
EX: 0.1mm
Loosen the lock nut and adjust by turning the
adjusting bolt.
Valve Wrench
IDLE SPEED ADJUSTMENT
1.Warm the engine up to 60
Ċ
.
2.Remove the engine protector cover.
3.Insert both of vacuum gauges on the both of
vacuum holes.
4.Check the vacuum value of twin-cylinder
separately.
5.Adjust the differential vacuum within 20mm-hg.
6.Slightly turn the throttle grip for several times and
recheck if the differential vacuum is within
20mm-hg. If within and continue next step, If not
within and operate the step above again.
7.Adjust the idle speed to 1300±100rpm.
8.Slightly turn the throttle grip for several times and
recheck if the idle speed still stay at the specific
value. If rpm is at 1300 and continue next step, If
not and operate the step above again.
Bolts
＊
Inspect and adjust valve clearance while the
engine is cold (below 35
℃
).
Lock Nut
＊
After adjustment, rotate the crankshaft several
turns to make sure that the valve clearance is
correct.
Choke Rod
Special
＊
Check the valve clearance again after the lock
nut is tightened.
Vacuum Holes