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German Motorcycles

NSU 251 OSL

Production: 1933-1940 and 1947-1952
Units built: 1933-1940: 34,977 | 1947: 58 | 1948: 667 | 1949: 4,849 | 1950: 10,442 | 1951: 13,570 | 1952: 2,879
Engine: Single cylinder four-stroke, dry sump oil circulation
HP: 1933-1934: 9.0 (5000 rpm) | 1935:10.0 (5000 rpm) 1936-1940:10.5 (5070 rpm) | 1947-1952: 10.5 (5000 rpm)
Engine displacement: 242cc
Cylinder diameter: 64 mm
Piston stroke: 75 mm
Compression ratio: 6.2:1 max. 6.8:1
Valvetrain: OHV; two pushrods in one tube, giving the appearance of a vertical bevel drive shaft driven valvetrain
Carburettor: BING 2/22/16; pre-WW2 models with AMAL 4/017, GRAETZIN KE 20 or BING AJF 2/20
Transmission: 1933-1935: 3-speed, then 4-speed
Tyre size: 1933-1949: 3.00-19", then 3.25-19"
Weight: 126 kg
Length: 2000-2040 mm
Gas tank volume: 11.5 ltr
Fuel consumption: 2.7 ltr/100 km
Top speed: 95-100 km/h
General information: enclosed and fully sealed cylinder head introduced in 1938 (until 1937 the valve springs etc. were fully visible)

Information supplied by Hartmut Schouwer


Ducati Gowanloch
Ducati Gowanloch
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