Yes I did just buy the tractor. I am familiar with the operations of it. The variable speed works just as it should, when it gets to full throttle. It is doing the same thing as the gentlemen described in first post. Does calibration have to be done by a cat dealer? I called them today and it is going to be around two weeks before they can get to me. How many calibrations is there in the drive system? Is this something I can do, Or does it have to be done through the dealer?