CF MOTO CF500-5, Service Manual, Page: 225 / 254

12 Ignition System
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Troubleshooting
Engine cannot be started. Check fuel and aire channels for any faults; if the fuel and air channels are normal,
check the ignition system.
Inspect ignition system for the following items:
1
,
Spark inspection:
Check in the following steps: Remove spark plug, remove spark plug cap, set high tension flexible cable end
to earth, check spark arc. It is normal if spark arc is more than 8mm, while is is weak if it is less than 5mm.
If the spark is normal, check the spark plug.
A faulty spark plug may be caused by the following reasons:
(1)
Spark plug is too wet and drowned. This is because the gas mixture is too thick. Cut the fuel and start the
engine several times.
(2)
Carbon deposit on spark plug--Mixture too thick or oil combustion in the combustion chamber. Clean and
burnish the spark plug.
(3)
Cracks with spark plug insulator.
(4)
Spark plug electrodes have short circuit or it is obstructed between negative pole and thread or positive pole
and input end.
2
,
Faulty spark includes: no spark and weak spark.
Inspect the following aspects if there is no spark:
(1)
Inspect ignition coil with multimeter or measurement in the following steps:
Measure primary bobbin resistance, usually it is about
.
Measure secondary bobbin resistance, usually it is about 4.2K.
Measure damp resistance, usually it is about 5K.
(2)
Check CDI if it is out of service.
(3)Check ignition circuit. Usually the voltage between black wire and earth wire (green) should be 12V. If there
is no voltage, check from the battery possitive terminal to the end of black wire.
(4)Check the cable: check if there are any faults from the input of trigger signal (output of magneto pickup) to
output (CDI terminal) and ignition output wire (black/yellow).
(5)Check stop switch. When switch is at the ignition position, black/white wire should be cut with green wire.
In case of weak spark, check the following:
Check CDI.
Check ignition coil and secondary coil whether there is short circult, or fault with the damp resistance.
(6)Check if the input of trigger signalis reverse.