I havent personally did it to a motorcycle tire yet but should be the same , using a white paint pen then spraying over a clear enamel or acrilic paint that adheres to rubber , you can keep the white lasting for a couple of years , did them on a semi trucks tires... try painting all thoes letters and having them fade and redoing them every so often.... anyway hope that helps if anyones wondering how to keep the color of the letters , it also gives the bikes tire a constant wet look when not dusty. Cycle tire may wear off faster tho.