Motorcycle Repair/Intermittant spark on 1996 KDX 200
QUESTION: Hi Wayne,
I just bought a 1996 KDX 200 and it has been running fine but all of a sudden, it wouldn't start. I took the spark plug out of the head and kicked it and saw no spark between the gap so I replaced the spark plug. That didn't help so I started checking the electrical wiring thinking that the kill switch might be broken so I disconnected it and I started getting spark again. I rode it for 15 minutes and the bike died again with the same symptoms. I am thinking that the ignition coil might be intermittently working but before I just randomly start replacing parts, I wanted to test the ignition coil. This bike does not have a key to start it and is only uses kick start. The ignition coil only has one blue wire going to it and I'm wondering how I would test to make sure the ignition is good or bad? Would I check to see if there was voltage on the blue wire? When does voltage need to go down the blue wire and how does the magnito play into this? Any help would be greatly appreciated.....thanks, John PS-I have attached a picture of the ignition.
ANSWER: Hi John,
The coil should have some voltage going to it every time you
kickstart it. This will be hard to check with a normal multimeter
but it should have a reading. You can just connect a battery
momentarily to the coil and see if you get a spark
with the plug grounded to the engine.
There is also a pulse or trigger coil on the stator and
usually a charge coil that charges the capacitor in the
The pulse is very small like 1 or 2 volts and the
charge coil can be quite large voltage.
I can get you some specs and post them a bit later
today if you want.
---------- FOLLOW-UP ----------
QUESTION: 2 questions: If I try connecting a battery momentarily to the coil to check for a spark as you suggest, how many volts does the battery have to be?
Also, what is a "stator" that you mention and how does that connect to the ignition?
Thanks for your help on this.
A quick touch to the small primary wire of the coil with a 6-12 volt
battery should produce a spark on the plug. Ground the coil frame.
If your bike runs occasionally it might be hard to pinpoint the problem.
Some problems only show up when the bike is hot.
Coil primary reads about 1.0 ohms to ground.
The stator is the group of coils under the flywheel which is
under the round cover on the left side of the engine.
You should see some wires coming out of the engine case
just above the cover.
The white/red wire is the power to charge/fire your CDI ignition
module which energizes the ignition coil to the spark plug.
The yellow wire is the power to your lights.
The black wire is the ground for both these other coils.
If you have a multimeter:
White/red to black is 304-456 ohms
Yellow to black is 1.76-2.64 ohms
Here is a wiring diagram of your ignition system:
To replace the stator coils your would need a flywheel puller.
Look online for these.
Things to try:
Kickstart and check for power between the white/red to black wires when it stops.
Check the ohms on the stator coils when the bike stops running
to see if they have changed.
If you think the stator coils are working then you will have to check
or replace the ignition coil and lastly the CDI ignition module
under the fuel tank behind the rad cap.
Another thing to do is remove all the connectors and clean them
with some electronic spray cleaner.
Check any connectors and grounds on the ignition parts.
Often a poor connection can give out when warm causing
intermittant problems. Check the coil grounds to the frame
and spark plug cap also.