scooter description

The classic scooter design features a "step-through" frame and a flat floorboard for the rider's feet. This design is possible because the scooter engine and drive system transferring power to the rear wheel is attached to the rear axle or under the seat. Unlike a motorcycle, where the engine is mounted on the frame, this front-hinged arrangement allows the engine to swing vertically together with the rear wheel. Older Vespas, most vintage scooters and some newer retro models have axle-mounted engines with a manual transmission and the gear shift and clutch controls built into the left handlebar. Most newer scooters use a Continuously Variable Transmission (CVT).

Unlike most motorcycles, scooters usually feature bodywork, including a front leg shield and body that conceals all or most of the mechanicals. There is often some integral storage space, either under the seat, built into the front leg shield, or both. Most modern motor scooters have smaller wheels than motorcycles, 12 to 15 inches (30 to 37,5 cm) in diameter, though maxi- and big-wheel scooters may have larger wheels. Most scooters have smaller engines than motorcycles, 50 cc to 400 cc with a single cylinder, though larger models have twin cylinder 400 to 800 cc. motors.

Most jurisdictions have no legal definition for "scooter". Most states and countries classify scooters having engines smaller than 50 cc as mopeds, and subject them to lower safety restrictions and licensing fees. Scooters above 50 cc are usually legally considered motorcycles, although some states have an in-between definition for motorized bike for scooters and motorcycles between 50 and 150 cc.
Flyscooter Il Bello, a modern scooter with a classic look
Flyscooter Il Bello, a modern scooter with a classic look

Until recently, most modern motor scooters came with air-cooled two-stroke cycle engines with automatic two-stroke oil injection although some of the higher spec small ones and large ones are water cooled such as the Honda FC50 or the 2002 Yamaha YQ50s. Scooters increasingly have four-stroke engines to meet stricter emissions controls. Trends around the world have seen new variations on the classic scooter, some with larger engines and tires. High-end scooter models now include comprehensive technological features including cast aluminum frames, engines with integral counter-balancing, and cross-linked brake systems. Some of these scooters also have comfort features such as an alarm, start button, radio, windshield, heated hand grips and full instrumentation (including clock or outside temperature gauge).

In an effort to reduce emissions, there are now LPG powered scooters that run on liquefied petroleum gas (LPG) instead of petrol or diesel. High-powered electric road scooters are on the horizon since small electric motorcycles like the Vectrix, e-max, and the eGO have been released.

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