Hey guys. I don't know the ins and outs of this rocket kit, but I do know Jerry (the owner and designer). He is a good guy with a lot of knowledge. Give him a call and ask him about his motors that he builds for yamaha snowcross racers. Especially ask him about the guy that races in alaska that he ships too. He makes pretty good kits, and I they do run on pump gas. These rocket kits also included clutching. I have ridden his personal sled, and it flys. He said he would warranty the engine work he did on my viper, so I would think the same would apply here, but I would definetly get it in writing to be safe. Money is money.