Try Spectro Heavy Duty Platinum 6 speed, 75-140wt. I immediately noticed a difference when I switched. It also helps finding neutral when your ride is cold. It may be tough to find locally but you can order it via Amazon. I have never seen it at an H-D dealership because they want to push their brand, but, I have seen Redline Shock Proof on their shelves which would be my second choice. I think you'll be surprised with either, and, it should quiet things down a bit. My second choice would be Redline.