KYMCO MX’er 125 Service Manual page 27

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
1-25
Symptom
Correct timing
Correctly adjusted
No air leak
Good spark
Incorrect timing
Incorrectly
Air leaks
Weak or inter-
mittent spark
MX'er SYSTEM
Probable Cause
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