Motorcycle fairing

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This article is about motorcycle design. For other uses of "fairing", see Fairing (disambiguation).
Suzuki GSX1300R hyper sport bike
Suzuki GSX1300R hyper sport bike

A Motorcycle fairing is a shell placed over the frame of some motorcycles, especially the racing motorcycles and sports bikes, with the primary purpose to reduce the air drag. The secondary functions are the protection of the rider from airborne hazard and wind-induced hypothermia and of the engine components in the case of an accident. There may be the front fairing, as well as rear fairing assemblies. A motorcycle windshield may be an integral part of the fairing. [1]

[edit] Types

  • Dustbin fairing: A single-piece all-enveloping, fully streamlined shell resembling the nose of an aircraft, sometimes politely referred to as "torpedo fairing". It dramatically reduced the frontal drag, but it was banned by FIM from racing in 1958, because it was thought that the frontal point of wind pressure made them highly unstable even with small amounts of yaw.[2] Other reasons cited were to ensure the adequate steering range (steering lock) and stability against crosswinds. FIM regulations forbid streamlining beyond the wheel spindles and require the rider's arms and legs to be visible from the side.[2]
A 1961 BMW racing sidecar with "dustbin"-like front fairing
A 1961 BMW racing sidecar with "dustbin"-like front fairing
  • Dolphin fairing: It was called so because in early models the front wheel mud guard streamlined with the rising windshield part of the fairing resembled the dolphin's beak from the side view. They had become the norm since the ban of the dustbins.[2]
Harley-Davidson police motorcycle with "batwing" fairing
Harley-Davidson police motorcycle with "batwing" fairing
  • Full-fairing: Bodywork that covers both upper and lower portions of the motorcycle, as distinct from a half fairing, which only has an upper section, and the lower half of the motorcycle is exposed. The fairing on a race or sport bike is meant as an aerodynamic aid, so the windscreen is rarely looked through. If the rider is sitting up at speed he will be buffeted by his rapid progress through the air and act as a parachute (slowing the bike) while if the rider lies flat on the tank behind the windscreen he generates much less aerodynamic drag. The high windscreen and handle-bar width of a touring fairing protect the upright rider from the worst of this, and the windscreen is functional. Full fairings can also provide protection to the engine and chassis in the event of a crash where the fairings, rather than the engine covers and/or frame, slide on the road.

Originally the fairings were cowlings put around the front of the bike, increasing its frontal area. Gradually they had become an integral part of the design. Modern fairings increase the frontal area at most by 5% compared to a naked machine. Fairing may carry headlights, instruments, and other items. If the fairing is mounted on the frame, mounting equipment on the fairing reduces the weight and rotational inertia of the steering assembly, improving the handling. [2]

[edit] See also

[edit] References

  1. ^ Tony Foale, "Motorcycle Handling and Chassis Design" ISBN 8493328634 , Chapter 5: "Aerodynamics"
  2. ^ a b c d John Robinson, "Motorcycle Tuning: Chassis", ISBN 075061840X, p.132
  • P. E. Freathy, J. D. Potter (1979) "An Investigation of the Performance of the Motorcycle Fairing", University of Bristol, Dept. of Aeronautical Engineering
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