A motorcycle with a full fairing is not an unknown type of vehicle. These have been known for a long time under various names. Bicycles with a full fairing are called velomobile. They can be called 'Cabin Scooter'. In Europe after WWII many former airplane companies got into making three or two wheeled enclosed motorcycles with very aerodynamic bodies, one was the Messerschmitt an instance of which appeared in the movie Brazil. In Czechoslovakia they were called "dalnik".

Motorcycles have horrible aerodynamics. Still, they can get great gas mileage even with horrible aerodynamics. Some contests have been run which proved that adding a fairing to a motorcycle can give it tremendous fuel efficiency. The main key is improved aerodynamics.