Andrew, Try some of the easy things first. Have you washed the motor lately. Did water get in the spark plug holes. Pop off the boots and blow out any standing water. If the boots are tight sweat or water won't evaporate out and you will have rough riding. Also, weak fire to the plug, when was the last time the coil was replaced. Even though there is no moving parts, coils do get weak just like plug wires. A almost 20 year old coil can give some cars a new life. And, last but not least, the dreaded alternator, won't keep up. Have you tried our 140 Amp. It's a champ. But it would help if you have a good strong 850 amp cold crank amp battery. My $.02's worth. John 11004