[cricketo]

My hunch is that is a bad design. A better (though probably still not ideal) design would be to have two motor controllers getting input from the same throttle, but having a bit of a translation to account for the difference in RPM to speed mapping. Even with cheap non-programmable motor controllers that will be easy to accomplish by having a microcontroller taking the throttle input, then splitting it into two outputs with slight amplitude adjustment for the smaller wheel.

 

[cricketo]

Yes it is: rate of position change is speed; the rotational rate of an engine or a motor is routinely referred to - correctly - as speed. Rotational rate or speed is of course not linear rate or speed.


True, which doesn't matter even slightly.


I agree.


Again, that may be true but it it unimportant. Every motorcycle I've seen is only rear-wheel-drive, and almost all have gas engines; neither of those apply to this motorcycle, and that's okay, so why insist on using the front wheel speed? It really doesn't matter.

Cars use the driven wheel speed because the transmission was traditionally the easiest place to hook up a gear to drive a mechanical speedo cable. I don't know why motorcycles traditionally use the front hub... perhaps because the speedo is traditionally mounted on top of the front forks. All completely irrelevant to this electric motorcycle and its determination of speed from electronic signals from drive motors (or controllers).

I don't know if there is any benefit to the reading the actual ground speed when dirt biking, but that's one case where reading the speed from a non-driven wheel may be more accurate than from the driven wheel which is likely to lose traction and slip.