I sometimes do the same thing to tailgaters, if you insist on riding my rear bumper, I slow down so the distance between the tailgater and me is safe for the speed. I do give a warning first, like tapping my brakes 2 or 3 times, some people take the hint and back off, but those that don't find me slowing down until they get off my bumper.
thats much nicer then the warning I give
