I’m just catching up on this thread. not sure if it’s been mentioned. take off your drive wheels, pull off the wheel pulley and see it the bearing in the pulley actually free spins. I noticed a huge loss of range (nothing close to my calculation) when I used the TB AT wheels for a bit. Took everything off an noticed the plastic pulley bearing seat was not perfectly round and actually squeezed the bearing enough to seize up the bearing. I put those wheels on the shelf and am waiting for improved replacements from TB.