whats the ignition system you have on it? have you broke in the cam yet? if it just wont fire anymore it could be an ignition module. ignition modules tend to go bad unexpectedly.. start with basics though make sure everything is making good connection ... i ask if you have the cam broke in because if you dont.. simple way to see if you have any spark at all is pull a plug hook the wire up to it and hold it to a ground to see if you have any spark at all. Hope this gives you a place to start