I put a 70cc athena cylinder and head, performance crank, biturbo(promo county) and a 14mm bing carb on. I got it to run, but when your on it it is realy bogy, and you have to play with the throttle to go anywhere, I tried re jetting it and fiddling with the timing a little, but it still does it. When its on the stand it runs pretty nice, and cleans out on the top end, but when you ride it its bogy. I believe i started with either a 72 or 60 in it, and i know i have run a 56(current) 60 and 64, but they all have behaved pretty similar. Ive been primarily runing a champion 82c plug, but i don't know if perhaps that is too cold of a plug. What should I run and anyone got any clue. Would a 14mm carb realy bog it like this, shouldn't it run ok.