... bicycle engine kit,can put on mountain bike,beach cruiser,city bike,folding bike and so on , with EPA standard 50cc/60cc/80cc gasoline engine kit ... ,it can put on kinds of bikes such as mountain bike,beach crusuier,city bike,folding bike.the engine have different ... higher than 53USD .And we have best ones gasoline engine kit which pass EPA standard , we aslo have four stroke ...