ducar_rebuild
New Member
hi i have a air cooled prox 250 and every time i give it a good run it shoots out flames and back fires but thats when i back of the throttle. In the high revs its ok and then when i slow down the motor stalls. When cruising its fine. Ive cleaned carby, airbox,fuel lines,done valve clearences, change spark plug, re wired still does it but not so bad do you guys have any ideas what is wrong any help appreciated