Misfire

by Ed O'Gorman
(Port Charlotte, Fl)

I have a 2002 Kawasaki Vulcan 800 with 23,000 miles on it. Ever since I bought it it had a very rare what seemed like a misfire. The bike starts every time, idles perfectly and has great acceleration, and will run all day at speed with no problem. It's when I back off on the gas, I begin to get what sounds like a spit or a puff which I feel through the air filter cover, and the bike will start to chug and buck a bit till I give it more gas. Then it will run fine. I've had it to a repair shop, and they said it was caused by the ethanol in the gas, and to use sea foam which has done nothing. It is happening more frequently lately. Any advice on this problem would be greatly appreciated.
Ed O'Gorman