I bought this sled for 400 bucks thinking it was good to go, but now i'm in to it for 1500 hundred. It starts great half pull but seems to run on one piston although there is good sprark on both when it is given gas It bog's and won't move. I've replaced entire electrical system, rebuilt fuel pumps, rebuilt carbs, new top end, replaced crank bearings and seals(by pro), primary clutch is working mint. the motor has been completly rebuilt. I think the sled is CHRISTINE!!!! somebody please help me.. Note: I have had the sled up to 80 mph but when I turn around it bog's and won't move.