250X firing problem

[kingdingaling]

I've got an 87 250X with the following mods: bored oversize, Wiseco 11:1 piston,Web cam, ported/shaved head,400EX carb, DG race exhaust, K&N air filter, aftermarket CDI box. The problem I'm having is that the engine has become difficult to start, fouls plugs, sometimes won't start at all (no spark), and today it died on a trail ride and would not start back. Sometimes when it does the no spark thing, if you leave it alone a day or two, it fires right up and runs great. When we first built it, it would fire up on the first or second kick. Now it takes forever. I have swapped out the CDI box and it does the same thing. I just bought a new box and it did'nt fix a thing. I don't know if it's the magneto or the coil or something else. The reverse switch checked out fine. I bypassed the run/stop switch when we first built it and put a CR kill switch on it so that's not the problem. Has anyone else had this problem? Any ideas?

I have been impressed with the level of knowlege on this board so I am hoping someone can help. Just once I would like to be able to go riding and not have to be towed back home!!

Thanks,
Steve

[Randy H]

i have an 87 to
all stock engin and has been sitting out side for more than two years(go it for free form my neighbor) and it does not spark..what should i check first?

[nossquirrel]

Just a few hints as to what it may be. If you have a kill switch, like a pro designs, check that connection first. If you do not, then chances are your coil is bad. Wet conditions are a great killer for any quad, and with it being an 87, that would be the next cheapest route for you to take.

As for the dude that got the quad from his neighbor, if you have a buddy that has a 250x or 350x switch the cdi out. Basically after that you are in the same boat as the other guy, or worse with it sitting outside and all.