My 2 cents. A 250-350 W motor is for those folks that want a little assit in their bicycle ride. With 250W I can average 4 mph faster and climb much easier than I could on a bike without a motor. With these size motors you will need to use all your gears. IMOP a 500W and up motor gives you a motorbike and not a bicycle with assist. No work required just turn up the assist.