1
. GENERAL INFORMATION
1-23
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
Broken vacuum tube
Faulty or fouled spark plug
Faulty CDI unit
Faulty A.C. generator
Faulty ignition coil
Broken or shorted spark plug
wire
Faulty ignition switch
Faulty air cut-off valve
Damaged vacuum tube
Clogged or damaged air vent
hole
POOR PERFORMANCE (AT HIGH SPEED)
Inspection/Adjustment
Symptom
Remove spark plug and
install it into spark plug
cap to test spark by
connecting it to engine
ground
Check air cut-off valve
Check carburetor gasket
for air leaks
Correctly adjusted
No air leak
Air leaks
Incorrectly adjusted
Good spark
Weak or inter-
mittent spark
Good
Faulty
Incorrect timing
Correct timing
Check carburetor pilot
screw adjustment
Probable Cause
Check ignition timing
