There is a hub motor in each of the 2 rear wheels. I am considering buying one and doing some mods (mainly the controller) or making one from scratch. My main question is about the use of 2 motors in the rear. I am assuming that there is one controller working both motors. I have read somewhere that doing this produces an automatic "differential effect"....or not? The rear wheels are hinged so that the whole bike will lean into turns, just as a 2 wheeler would.