I have a 2002 r1150rt (with heated grips) and the throttle is extremely stiff and difficult to pull. The previous owner, a friend, said it didn't used to be like that then became stiffer over time. He didn't know what it was but preferred it like that so didn't do anything about it. The bike was just in at the dealer for annual service and I had them take a look at they had no clue what was causing it either and suggested to fix it to replace the distributor box and all cables and of course they wanted a pretty penny for it. Has this happened to anyone else? Any ideas on what would be causing it?