PA 15-46-- "Motorcycles have two or three wheels, handlebars and a seat that is straddled. Autocycles have three wheels and are fully or partially enclosed, and have a steering wheel, foot pedals and seat belts. A person with an "M" endorsement may ride motorcycles with 2 or 3 wheels. A person who only wants to ride a three-wheeled motorcycle can take a three-wheeled motorcycle class, and have a restriction on his or her "M" endorsement. This will be designated as "M3". Autocycles do not require any endorsement. Both motorcycles and Autocycles will be registered with motorcycle plates. An example of a three-wheeled motorcycle is a Can-Am Spyder.
An example of an autocycle is a Polaris Slingshot. There are other makers of Autocycles,such as Elio, that do not yet have a manufacturer's license in CT"