On previous bikes, including a Harley Road King and a 98 Valkyrie, I've used a belt sander on the tires when they get loud in turns. The tires on both those bikes would develop a sawtooth pattern where each tread block was higher in the front than in the back. This was most pronounced where the transition from the center of the tread toward the edges made a sort of ridge. Anyway, the belt sander really works. You're trying to restore the original profile as best you can. They're much quieter afterwards. I only used to do this once on a tire at about 2/3 of tread life, maybe 6k miles. You hold the belt sander at a 45 degree angle and let it spin the tire slowly while grinding away the high spots. Works best on the rear tire. I posted a thread on the Harley forum about it but the pics are gone after Photobucket changed policy and started charging money.
