More states legislatures should consider the Virginia proposal
"Operation of mopeds is prohibited on any highway where the posted speed limit is in excess of 35 miles per hour."
This stipulation would limit 50cc moped operation to more compatible traffic, negate the incentive for engine performance enhancements, and (in states that do not require a rear plate) maintain easy-to-spot moped enforcement . . observed on an over 35mph road, no rear plate, fair game.
Related Nevada report