My friend has a 1978 honda 550k. It has the pd46c (i'm pretty sure) style carbs (77 & 78) The bike idles perfectly. He has cleaned out the carburetors several times and adjusted the points. The problem is that if you throttle up to fast once in second gear the bike starts missing real bad. He's done everything he can think of including riding with the gas cap open but cant get it to stop. Any ideas? I'm thinking float height, jetting, or needs colder/hotter plug.