Just started to misfire one day

I use the stock CDIs, but some folks like the expensive type. I've never tried one, so can't say if there is any difference.
 
i tested both of my cdi's and it seems like both of them have gone dead. Is it possible that my original and a replacement went dead after not much use.
My troubleshooting procedure is simple these days.

Disconnect everything.

Ohm the black magneto wire to a head bolt, it should read a dead short.
If not, check the ground tab on the magneto.
Note:
The new skyhawk CDI's have no white wire, ground is the lower connector but it has a wire from it to ground.

Old style mags with a white wire have a tab out of the mag that solders directly to the mag base and they can come loose, just hold it down and re-solder.

Ohm the magneto from the black and blue wire, 320-380 ohms is ideal, an open or dead short means a bad magneto if the wires are connected.

Ohm the CDI in the 10K-20K scale.
Red+ meter probe to CDI black wire.
Black- meter probe to the spark plug cap.
You should get about 6.9K ohms.

If not it could be a bad wire or cap.
Unscrew the plug wire at the cdi, use pliers or even cut it off and dig the junk out if need be and do the same test above again to the cable screw on the CDI.
If that works get a new wire and plug cap, if not you have a bad CDI.

If all of that is good there is only one thing left, the magnet.

That was indeed the problem with this repair on a new build with a 2014 gasbike.net front page engine kit.

When you pull the 4 bolts out of the magneto mount it should slam itself against the magnet, I mean to the point where it is hard to even get your first bolt in.
A weak magnet that lets you move the mag around pretty easily is not strong enough to create a spark which is what this repair had.

Magnet replaced, problem solved and my repair is done.
 
why would you say that the rocket racing isnt that great. do you know the differences between the jagurar and the lightning that set them appart from each other.
 
to kcvale

the magneto is good. i just tested that all out and its testing perfectly. i just ran a current through my cdi with a trickel charger and tried to get a spark and didnt get anything. so im only guessing, but i think the problem lies within cdi
 
the rocket racing cdi uses cheap parts
the hd lightning has a more aggressive timing curve than the jag does
 
to kcvale

the magneto is good. i just tested that all out and its testing perfectly.
i just ran a current through my cdi with a trickel charger and tried to get a spark and didnt get anything. so im only guessing, but i think the problem lies within cdi
Of course you didn't get a spark from a DC trickle charger, the CDI needs an AC pulse to fire.

Are you sure you followed all those steps?
If your CDI ohms out to the plug cap you either have a crap plug or a weak mag magnet.
 
to brute

do you have an hd lightning or a jaguar

to kcvale

well i hooked it up to a tester and i could never get a good reading it would always jump around even if we weren't doing anything to it.
 
I use an HD Lightning, but the Jaguar is better if reliability is a bigger concern than raw horsepower.
 
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