In the U.S., a motor scooter is legal on highways so long as it can maintain the posted speed limit and is street worthy (which most bikes are, with turn signals, lights, etc.) In fact, it's a great way to get around.
In Nebraska it is posted by all On Ramps to the highways that there are a number of vehicles/things not permitted on the highway, one of which is "Scooters less then 10hp"
In the UK motor scooters or mopeds are allowed on a public highway so long as the vehicle is road worthy and has in place correct vehicle insurance and a current MOT. a highway is any road or street etc, but a scooter is not allowed on a Motorway as a scooter normally has its speed limit capped at 30 miles an hour which is considered a hazard on a 70 mph motorway. The Highway code sets out all of the rules relating to the use of vehicles in the UK.
