2 things- first, check the wiring, especially on the side of the airbox where it can get melted by the exhaust, if not in the clips on the airbox. next, you can do some tests on the cdi. if you have no spark, put the switch in kill and kick it over, then back in run and see if that helps any. then, smack the cdi with the butt of a large screwdriver, to either get it started, or while it's running to try to make it glitch.