I use S-100 on my motor home and it removes all of my black streaks and cleans perfectly with no effort.Nothing better for removing dried bugs on front of unit including windshield. You can buy it on-line or at your local Harley Davidson dealer. Spray it on, (Like blood spreading, just a mist will do it) wait 3 to 4 minutes and easily scrub off anything. You will see a milky runoff that has to be rinsed good. It will also coat any metal surface to stop any rust or corrosion of any kind. Try this I think that you will be happy. Color fading? try wiping down with transmission fluid.