kx80 ignition trouble

[newtoyforthekids]

I am unable to get a spark on this newly acquired 1988 vintage Kx80.

The stator coils are good - as I recall there was about 210 ohms and about 10 ohms on the two coils (also verifies good out to the connectors up on the frame). Stator coils condition is also verified by the voltage pulse I measured at the connectors when the flywheel spins.

The ignition coil is good. Primary and secondary windings show proper resistance and a 1.5 v battery on the primary produces a spark on the secondary.

Spark plug looks good (not fouled) and I also tested the bike for spark using a known good plug - no spark.

The CDI box is the mystery in my mind. How can I test this for proper function? I have a degree in electrical engineering but as yet, do not know the workings of this beast.

I find no kill switch on this bike. Is there anything else I am missing here?

Thank you very much - your help will make some boys very happy.

 

[helio lucas]

hi,
you will need a service manual to test the cdi. they have the proper procedure to test it along with all the correct values you might need to know.
it is great information for periodic maintenance as well for repairs. it will paid for itself shrotly.

if you have access to a borowed cdi, it will be great.
good luck :cool:

 

[gunnershank]

I am having the same problem on my KDX 420. Just replaced the old corroded coil and next is the CDI. From what I've heard the CDI is very sensative and can burn up if shorted somewhere really fast. I have mine on order, will let ya know if it was the problem.