I am pretty sure it will work on the harley windshield, all you have to do is scuff the windshield down with some 400 grit wet/dry sand paper and wet sand it. if your wiery of 400 grit, move up to 800. and then spray it with the night shades. My friend has used this on his honda accord tail lights and they look really nice and clean. But I still like the way I did mine, mixing automotive clear coat and dropping a few drops of black in it, and it will come out REAL smooth and shiny.