50cc/60cc/80cc bicycle engine kit,can put on mountain bike,beach cruiser ... so on , with EPA standard 50cc/60cc/80cc gasoline engine kit ,it can put on kinds of bikes such ... mountain bike,beach crusuier,city bike,folding bike.the engine have different quality ,cheap ones just 50 USD(but ... have best ones gasoline engine kit which pass EPA standard , we aslo have four stroke 50cc motor engine ,if you need , ...