Pretty common with the whipple and not a cause for worry. Kendall loosened up my pulley just a tad and the noise is completely gone, that was 2000 miles ago. On a cautionary note, all whipple users should check the lubricant level through the front glass viewer of the SC to make sure it is the belt and not the internals. If you want to make sure the chirp is from the belt, pour a a few drops of water on the belt and the noise will go away. Incidently, whipple trims the belt to the proper width.