I remember when I was at the local performance bike shop and I bought a new wheel on impulse (when I knew I could get a free one at Sports Authority). I think the guy working there said it was a freewheel. When he was transferring the gears to the new wheel, he put it in a vice and twisted the wheel around the vice (with the gears held in place by the vice). I ended up returning the wheel because it was 126mm spaced rather than 135mm that I needed.x