This an overview of the common features of a scooter. Most smaller scooters operate the same; they are automatic, electric start, kick start backup, step through design, have a side and center stand, storage under the seat, have front disk and rear drum hand brakes(some have front and rear disk), can carry 2 people, and 50cc versions typically go between 3045mph. There are 2 main engine types: 2 cycle, which are generally slightly faster but they burn more fuel and pollute a little more because the engine is lubricated by burning oil. The other type is a 4 cycle, which like a small car engine. They burn cleaner, get a little better fuel economy, and require the oil to be changed periodically. The down side of these engines is that they are slightly heavier and aren't quite a powerful on average. Most engines now are 4 cycle.