Yea, I had that noise as well. Started form 4800 till about 6000. When I took it in to the dealer, they had discovered it was the Cam Chain Tensioner. It sounds like a loose key chain was hitting the triple tree, for lack of a better description. But all is well, it was replaced under warranty. There have been numberous cases about this, Cycle World did a piece in their reader responses area, and it should easily be resolved. Good Luck!