I really like the look of this thing! Amazing engineering!
But I have a couple of questions:
-when you reverse the whole gearbox, then the motor will spin the wrong way? You'd need a 4 & 3 gear solution in order to "get the best of both worlds? Or am I missing something? (Is the motor and spur "reversed left/right" as well then?)
-and why not simply but ballast in the rear for more grip? It shouldn't have to be necessary to move the motor...