Recumbent bicycle in the context of "Bicycle fairing"

A velomobile (/ˈvɛloʊmoʊˌbil/), velomobiel, velo, or bicycle car is a human-powered vehicle (HPV) enclosed for aerodynamic advantage and/or protection from weather and collisions. Velomobiles are similar to recumbent bicycles, pedal go-karts and tricycles, but with a full fairing (aerodynamic or weather protective shell) and are not to be confused with purpose-built mobiles for speed records. Fully faired vehicles with two wheels are generally called Streamliners and have set many speed and distance records.

Though fast in their own right, velomobiles are considered much more suitable for the street than two-wheeled streamliners. Using three or more wheels can have advantages for everyday use, including the ability to stop and start unaided, better stability, cross-wind handling, etc., though there are arguments made that the multiple track machines (three or more wheels) have aerodynamic disadvantages due to the drag of the extra wheels and the surface contact points. In practice though, velomobiles continue to be close to their two-wheel cousins in performance.

A streamliner is a vehicle incorporating streamlining in a shape providing reduced air resistance. The term is applied to high-speed railway trainsets of the 1930s to 1950s, and to their successor "bullet trains". Less commonly, the term is applied to fully faired upright and recumbent bicycles. As part of the Streamline Moderne trend, the term was applied to passenger cars, trucks, and other types of light-, medium-, or heavy-duty vehicles, but now vehicle streamlining is so prevalent that it is not an outstanding characteristic. In land speed racing, it is a term applied to the long, slender, custom-built, high-speed vehicles with enclosed wheels.

Road cycling is the most widespread form of cycling in which cyclists ride on paved roadways. It includes recreational, racing, commuting, and utility cycling. As users of the road, road cyclists are generally expected to obey the same laws as motorists, however there are certain exceptions. While there are many types of bicycles that are used on the roads such as BMX, recumbents, racing, touring and utility bicycles, dedicated road bicycles have specific characteristics that make them ideal for the sport. Road bicycles generally have thinner tires, lighter frames with no suspension, and a set of drop handle bars to allow riders to get in a more aerodynamic position while cycling at higher speeds. On a flat road, an intermediate cyclist can average about 18 to 20 mph (29 to 32 km/h), while a professional rider can average up to 25 mph (40 km/h). At higher speeds, wind resistance becomes an important factor; aerodynamic road bikes have been developed over the years to ensure that as much as possible of the rider's energy is spent propelling the bike forward.