In Wisconsin the law states that A Moped is:
1. Any of the following vehicles (excluding a tractor) capable of speeds not more than 30mph with 150lb. rider on a dry, level, hard surface with no wind, a power source as an integral part of the vehicle, and a seat for the operator.
2. A bicycle-type vehicle with fully operative pedals and an engine certified by the manufacturer at not more than 50cc.
3. A Type 1 motorcycle with an automatic transmission and engine certified at not more than 50cc.
Mopeds/Scooters same damm thing in WI