KYMCO 150 MXU -, Service Manual

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1
. GENERAL INFORMATION
1-34
ATV 150/125
POOR PERFORMANCE (ESPECIALLY AT IDLE AND LOW SPEEDS)
Faulty CDI unit
Faulty pulser coil
Mixture too rich (turn screw
out)
Mixture too lean (turn screw in)
Deteriorated O-ring
Carburetor not securely
tightened
Damaged insulator rubber
Faulty or fouled spark plug
Faulty CDI unit
Faulty A.C. generator
Faulty ignition coil
Broken or shorted spark plug
wire
Faulty ignition switch
Remove spark plug and
install it into spark plug
cap to test spark by
connecting it to engine
ground
Inspection/Adjustment Symptom Probable Cause
Check ignition timing
Check carburetor gasket
for air leaks
Check carburetor air
screw adjustment
Correct timing
Incorrect timing
Correctly adjusted
No air leak Air leaks
Good spark
Weak or inter-
mittent spark
Incorrectly adjusted