|Manufacturer||Vincent HRD Co., Ltd|
|Engine||998 cc OHV, air cooled, pushrod V-twin|
|Power||45 hp @ 5200 rpm|
|Wheelbase||55.5-inch (1,410 mm)|
|Fuel capacity||3.75 gals|
The Vincent Rapide is a motorcycle designed and built at the Vincent works in Great North Road, Stevenage, Hertfordshire, England, during the Second World War and released to the press before end of hostilities. The prototype was the Series A 47.5° V-twin launched in 1936. With 6.8:1 compression, it produced 45 bhp (34 kW). It is often purported that Phil Irving was trying to find a replacement for the 500 cc Vincent Comet engine. There were two blueprints on his desk, and one had fallen on top of the other, to demonstrate a "V" formation. There is no evidence to prove this, however. Its frame incorporated the first cantilever rear suspension, used on all subsequent Vincents. Other innovations included a foot gearchange instead of a hand-operated gearlever, a four-speed gearbox instead of two or three and a side stand.
The high power meant that the gearbox and clutch did not cope well. and it was developed into the ‘Series B’ which had internal oil pipes and the gearbox integrated with the engine casting (Unit Construction). The angle between the cylinders was increased to 50° instead of the 47.5° of the Series A engine, which allowed the use of the engine as part of the frame. The Rapide had ‘’Girdraulic’’ front forks and triangulated rear springing to prevent front end twist under hard braking. and the cantilever rear became the most widely used form of rear suspension for motorcycles after 1980. Brakes were dual 7-inch (180 mm) single-leading shoe (SLS), front and rear.
A more modern hydraulic shock absorber and spring assembly later replaced the old twin springs and friction damper. The rear seat was supported by a sub-frame down to the rear frame pivot point, providing a semi-sprung seat with 6 inches (150 mm) of suspension. The Series B had a Feridax Dunlopillo Dualseat, and a tool tray under the front. The Series "B" also had an inline felt oil filter instead of the metal gauze of the Series "A".
Vincent used quickly detachable wheels, making wheel and tyre changes easier. The rear wheel was reversible, and different size rear sprockets could be fitted for quick final-drive ratio changes. The brake and gear shift were adjustable for reach to suit individual feet and the rear mud guard was hinged to facilitate the removal of the rear wheel.
The Series C, which Vincent produced from 1949 until 1954, featured a 998 cc, 50-degree V-twin that put out between 45 and 55 horsepower, depending on the state of tune (Rapide or Black Shadow). Period tests demonstrated that the bike was easily capable of speeds in excess of 100 mph.
The letters HRD were discontinued in 1950. Vincent were trying to enter the American market, and did not want any confusion with Harley-Davidson (H-D). Falling sales of expensive motorcycles caused closure in 1956. Vincent refused to compromise on quality, which kept the price up. It has often been said that the firm was guilty of "over engineering". One comment made about this was that "Vincent is a solution in search of a problem."
A development of the Rapide engine, the Picador, was developed as an aircraft engine for lightweight aircraft. With a capacity of 997 cc, and weight of 200 lb, the engine gave 65 bhp. The engine was similar to typical Vincent practice, with two air-cooled cylinders in V-formation, and with the cylinders offset to improve cooling of the rear cylinder's exhaust valve. The valves and their rockers were driven by gear-driven overhead camshafts. Unusually for an aircraft engine, the engine was mounted in the same orientation as the motorcycle, with the crankshaft transverse. An oilbath chain primary drive and a bevel gear drove the propeller with a 2:1 reduction from the engine's 5,000 rpm. Mechanical fuel injection was used, driven from the propeller shaft.
- Vincent Motorcycles
- Vincent Black Shadow
- List of motorcycles of the 1940s
- List of motorcycles of the 1950s
-  Dropbears Histories (Retrieved 22 October 2006)
-  IanChadwick Vincent (Retrieved 22 October 2006)
- The Vincent, accessed 2005-05-03
-  TheVincent Models and Fittings (Retrieved 22 October 2006)
- Clement Salvadori (March–April 2007). "Riding the Big Sur on a 1950 Vincent Series C". Motorcycle Classics. Retrieved 2010-10-27.
- "POWER for ULTRA-LIGHT AIRCRAFT". Flight: 721–724. 5 June 1953.
- "Guided Midget". Flight: 254–256. 28 August 1953.