Harley-Davidson Model 7D
The Harley-Davidson Model 7D of 1911 was the second two-cylinder - Motorcycle of the American manufacturer Harley-Davidson and for the company a major advance in motorcycle.
History and technology
The previous model 5D was a failure in every respect, technically with sniffing valves behind the times, difficult to start and no buyer demand.
The engine dimensions of the previous model with bore (76 mm), stroke (89 mm) and displacement 811 cm³ were retained. The engine control was now carried out with an underlying camshaft for the exhaust and intake valve according to the IOE system . Equipped with a Bosch - magneto equipped and Schebler carburetor 45-degree V-engine is a power of 6.5 hp reached. This engine concept remained unchanged in the program until the "Flathead engines" were introduced in 1929.
The automatic belt tensioner, patented by William S. Harley , prevented the drive belt from slipping when wet. The wheelbase of the 28-inch machine with tires was 1435 mm. The top speed was, depending on the author, 55 to 60 mph (89-97 km / h) and was fair for the competition; Braking was done with a band brake on the rear wheel. The machine was well designed and the quiet running noise of the engine in connection with a silencer was advertised by the manufacturer as " The Silent Gray Fellow ". It is estimated that around 3,500 were built of the model, which was only supplied in "Renault gray" and was available for 300 US dollars at the time. On October 21, 2006, a Harley-Davidson 7D sold for $ 187,000.
Web links
Individual evidence
- ↑ Jerry Hatfield: Standard Catalog of American Motorcycles 1898-1981. Krause Publications, 2006, ISBN 0-89689-949-7 , p. 118.
- ^ Guggenheim Museum New York : The Art Of The Motorcycle. 2001, ISBN 0-8109-6912-2 , p. 117.
- ↑ Tod Rafferty: Harley-Davidson. 1st edition. Motorbuch Verlag, Stuttgart 1997, ISBN 3-613-01796-2 , p. 19.
- ↑ The Vintagent (accessed on 14 March 2013)