Originally Posted by Super rider
Did you ever get an answer to this? I have the same problem. Just installed mine with the converter cable and it's way off. It's over by like 15mph. I was wondering if there was a way to calibrate it as well.
This concerns me as well. I haven't installed mine yet but I was looking forward to the direct pick-up sensor accuracy.
You would think that there is a ratio adjustment that would work for either speed sensor. The airhead alone comes in 3 or 4 different speedo ratios. If nobody has figured this out by the time I mount mine I will call acewell customer service.