KYMCO 2006 MXU 500 Off-Road Owner's Manual page 221

1
. GENERAL INFORMATION
POOR PERFORMANCE (AT HIGH SPEED)
Inspection/Adjustment
Check ignition timing
Check valve clearance
Check fuel pump for
fuel supply
Check carburetor jets
for clogging
Check valve timing
Check valve spring
tension
Symptom
Correct timing
Correctly adjusted
Incorrectly adjusted
Fuel flows freely Fuel flow restricted
Not clogged
Correct
Not weakened
Faulty ignition unit
Incorrect timing
Faulty pulser coil
Improperly adjusted valve
clearance
Worn valve seat
Empty fuel tank
Clogged fuel tube or filter
Clogged Fuel tank cap breather
hole
Clogged Clean and unclog
Cam timing gear aligning marks
Incorrect
not aligned
Weak spring
Faulty spring
MXU 500
Probable Cause
1-38