Motorcycles, Snowmobiles, Go-Carts, ATV's and Golf Carts - 70cc mini ATV no spark ?

I have atv with a no spark issue here's the story.

I bought this avt 1 year ago for the kiddies, on the last day of school this year (june25th) it was stolen from our property. To make a long story short. We did the usual stuff.. police report, fliers around our town. As it turned out another kid from the neighborhood had his dirt bike stolen also and we were able to recover both bikes without the police help. We got them back the second week of August, well the kiddies are back in school and I still don't have it running... They messed it up pretty good.

When I got it back from the punks that stole it it was running, the ignition was missing and the wire harness was messed up pretty good but you could jump the solenoid with a screw driver and start it.

The problems started when I tried to wire in a switch in place of the ignition, I blew a couple fuses and heard a weird noise when I hooked up a wire (obviously wrong) and now no spark. !?

So here's what I've did so far and still have no spark...

If you goto zstar.com under 70cc atv you will see the electrical system on this bike is pretty basic.

So far I've replaced the ignition key switch, the wire harness, the cdi box, the rectifier, and I just ordered a alternator.

So you see I've replaced every electrical component except for the coil, when I put my voltage meter at the coil wires I see no voltage.

I'm hoping when I get the alternator in next couple days we will have spark again.

Amazingly all the parts listed above cost me less than a hundred bucks plus a new battery I bought for it in the spring (before it was stolen) fifty bucks.

The solenoid was also not triggering so it was replaced with a spare one from a lawn tractor and works fine now.

There are two safety switches on this bike, both were in place and also bypassed by being shorted. Still no spark or voltage at the coil.

So am I missing anything here !? Will I get spark this time !?


Thanks for any help you can offer.
Cheers Wayne.


edit: There is a four wire plus ground harness coming from the alternator when I put my voltage meter on them and crank the engine I see 40 to 50 volts ac on a couple of wires and 4 or 5 volts on the others... if this helps ??

I have a feeling you blew the cdi box that you replaced. For $15.00 you can't beat the price, as long as you can call it something that has CDI in it. You should have current at the coil, though with the switch on. The CDI box will discharge the spark with the capacitor. With that setup you normally have a signal generator coming off the the crank (or on the engine somewhere) to trigger the discharge = spark.

There are a lot of variations that can be plugged in, though. Like the small engine jobs have the ignition module with the built in capacitor. It pretty well does it all with a magnet on the flywheel = spark.

The way a straight CDI setup works is battery/switch/cdi box/coil. You plug in the safety stuff with circuit continuums/breaks . Then on the charging circuit = alternator (or stator)/rectifier/switch/battery. There is a way on some of the charging circuits to go from the rectifier into the CDI circuit.

Automotive jobs (these are not CDI's) normally have to have the battery in the circuit to start, but a lot of ATVs are setup to start off the kick without the battery in the circuit. Your's may be like that.

Will you get spark with the alternator change? - dunno.

Thanks for the reply,,,

How much voltage should be going into the coil.. 12 ?

Still waiting for the alt, probably have another go at it this weekend.


Cheers Wayne.

Sorry, Wayne I just couldn't say. Some coils are set up to start on full voltage (like the 12 volt), but run on lower voltages to reduce heat (death of all things electronic, especially with windings).

That must be a Chinese job = no telling what has been put together on that one.

One fella posted here with a little ATV about like that with electrical problems. That thing was a Chinese puzzle.