Please Help ny Boss just gave me a 90cc yerf dog Atv and the Damn thing does not spark. I have tried everything to get this thing to produce a spark. I even yanked all of the wires out attempting to trace the problem but no avail. Now I'm even more concerned. Do anyone know what would cause this thing not to spark or does anyone know how to bypass the BS and just get the thing running so that my son can be riding by Xmas? Any help please email me ASAP naamanjuhan@yahoo.com

BTW, I checked the coil with a test light while it was turning over and all the wires hasd power except for black and I was told that it's a ground. Thanks Joe

 

I have a 90cc yerf dog. It will not start unless you have the left brake pressed in.

 

A coil has 2 small wires on it. One wire should be "hot" with the ingition turned on. The other wire is intermittantly grounded as the engine turns over. (This is done by the points in older automobiles.) If this wire (presumably the black wire in your case) isn't opening and closing to ground, then that is your problem. So, the question is, what intermitantly grounds this wire? I'm not familiar enough with your atv to be more specific. I hope that this helps.

 

LOL, well I guess that's a mute point because I yanked all of the wires out today after 3 nights of fustration. My main thing is I want to see find a quick way to get this thing started to see if it is worth taken up space. It was given to me because my Boss son got to big for it so I wanted to have it running for my 4yr old for Christmas. Thanks Joe

 

Like I said you have to have the left brake handle pressed for it to start.

 

I have power to all of the wires coming from the coil except the black.

 

Even if I disconnected all of the kill switches on the left handle bar side?

 

i wish there was a way to post pictures (admin, are you listening?), so check out the link-
schematic

if you hotwire the black/white wire from the cdi box, then it bypasses any tether, key switch, etc. that may be "open".

obviously, make sure you have the spark plug firmly grounded when checking for spark, and you may even want to try a new plug to be sure.

if no spark, then check the secondary (plug wire resistance) between the plug cap and ground to make sure your cap is not bad. seen it happen on more than one occasion. dunno what the resistance should be exactly, I just know it won't run if it's open (inf resistance). i think it should be around 5k ohm or something like that.

if that seems ok, and the machine is at least a few years old and has seen muddy conditions, i'd guess your stator has taken a crap. cdis and coils don't go bad as often as people blame them to, but stators certainly do! about a benny to buy, and real easy to install (you really dont need a flywheel puller).

 

I'm not really familar with Quads myself but do they have or require stator and CDI boxes to crank just like sport and dirt bikes? I know it a dumb question but this bike is so tiny for all the electrical wiring, especially to not have lights.

 

The serial and paper work says that the bike was manued in 04. Every thing except the [lastic on this bike looks great! The tires still have the needle looking things on it(???) The only problem was that my boss left this bike in his backyard for over 6 months with a makeshift cover and when he did attempt to finally let hsi son ride for the summer it wouldn't fire.