well they could go 40 mph with 26in tires -36 tooth sproket andd 8000 rpm all day long .. Didnt you read the fine print? **** if you get the china ht to 11,000 rpm you could probably hit 50mph. What your motors are not that fast? Maby its agood deal then? HA HA LOL There must be a secreet to there sucsess, sombody's not talking..