My back one almost fell off but that was cuz my pony tank leaked gas all over it. The front one took some effort. I used dental floss and Goo-gone but most of the adhesive stuck. It took about an hour to remove that with Goo-gone and a micro cloth. When it was done the paint was severely rubbed out. After hearing all the paint stories I was mortified. But I grabbed some turtle wax buffing compound made for light scratches and buffed it out. Then hit it with some regular Turtle wax paste and it looks brand new.
I think doing it on a hot day or hitting it with a hair dryer first would have saved me a lot of work.