Can you describe them, what are they made of? I had a pair of foam covered metal grips on mine and they were a real bugger to get off. Could get the left one off just fine but the one on the throttle must have been put on with JB weld or somthing like that. Took it to the dealer for spring maintenance and had them change them. Kind of the cheesy way to do it but put a really nice set of ISO grips on. Much much better and my hands don't turn black anymore.