I had a mare with mine after accidentally reseting it. I have had to set mine up on 3 pickups with the wheel far smaller than it is its all I could do to get it right. Mine is run off afaik abs sensor and it seems it must read in a 2,3,2 resolution or there abouts so I've had to compensate in wheel size, either way with a bit of tweeking and gps speedo its easy enough to sort out.