It's the peened finish on all the new handlebars that make the grips spin. You can sand the grip area down to a smooth finish and then the rubber will stop squirming around. There is so much air space between the little bumps, that only a little of the grip actually contacts the bar. The only grip I've found that sticks to this kind of surface are ESI's. They're also some of the most comfy grips I've ridden, which is a major plus!,,,,BD