KYMCO NEXXON 50 Service Manual page 20

1
. GENERAL INFORMATION
POOR PERFORMANCE (ESPECIALLY AT IDLE AND LOW SPEEDS)
Inspection/Adjustment
Check ignition timing
Check carburetor air
screw adjustment
Check carburetor gasket
for air leaks
Remove spark plug and
install it into spark plug
cap to test spark by
connecting it to engine
ground
Check A.C. generator
Symptom
Correct
Correctly adjusted
No air leak
Good spark
Good
Incorrect
Incorrectly adjusted
Air leaks
Weak or inter-
mittent spark
Faulty
NEXXON 50
Probable Cause
Faulty CDI unit
Faulty pulser coil
Mixture too lean (turn screw in)
Mixture too rich (turn screw
out)
Faulty intake manifold gasket
Carburetor not securely
tightened
Damaged insulator rubber
Broken vacuum tube
Faulty or fouled spark plug
Faulty CDI unit
Faulty A.C. generator
Faulty ignition coil
Faulty ignition switch
Faulty A.C. generator
Damaged vacuum tube
Clogged air vent hole
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