I would go to duropower.com and buy the 29cc for $99.00,or the 26cc for $89.00.Ive already looked at them and i am going to buy either one or both and convert them.Probably at the end of this week.The ad also states single ring.I think the ones im talking about are 2 ring.Ther eeither the same motor if i remember right or there the Jen-fang or somthing like that and are better engines i believe.