ebonysresearch wrote on 11/11/10 at 17:29:46:are you blowing black smoke? is your oil level going down? can you shine a flashlight on the top of the piston and see a lot of carbon build up? I would check the coil with a meter. As was mentioned before, then look to see if you have power to the coil and a good signal. The coil is cheaper than the CDI box. If you pull the plug, shut off the petcock and plug the spark plug back into the spark plug wire and lay it on the head and turn over the motor...do you have spark?
Not blowing black smoke, starts fine with new plug, then "fouls" quickly. I get a weak spark at that point.