MM/Lehner Challenge

[BP-Revo]

AAngel, while most of what you said is true and very logical, I have to disagree with the whole dragster leaping back part.

That is no problem, but a common symptom of any sensorless system that get punched from a low speed. My 18T does it pretty often, it will go backwards a few inches and they shoot off like no tomorrow.

At a stop, the contoller has no way of telling where the rotor is. The motor isn't spinning, and therefore is not creating any EMF backpulses for the controller to read. When you punch it, the controller is simply guessing where the rotor is. Its usually right, or close enough where it will at the very least still move forward, but sometimes its wrong, which is why it rolls back a bit.