Just picked up a 2004 TW200 with only 600 miles on it. Didn't really take it through a decent test ride, but did notice a pulsing sensation through my foot on the rear brake pedal after I got it home and rode it around a bit more. Anyone have any idea what it could be? I know that it has been down before, but probably not at more than 10-20mph, based on the very light scuffing. I have owned a lot of other bikes and have never experienced this pulsing sensation before. Is something out of whack with the rear drum and, if so, how difficult is it to take it apart and have a look? Thanks.