Built around NSU's allround motorcycle platform, the 1941 NSU 251 OSL WH utilizes a 242 cc (14.8 cu in) air-cooled single cylinder, four-stroke layout. In factory specification, peak output is rated at 10.5 HP (7.7 kW) at 5,300 rpm. With a specific output of 43.4 HP per liter, the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.
On the scales, the 251 OSL WH measures 144 kg (317 lbs) dry, translating to a power-to-weight ratio of 0.07 HP/kg (13.71 kg per horsepower). The 11-liter (2.9 US gal) fuel tank supports practical everyday commuting and weekend road stints, while factory top speed is listed at 95 km/h (59 mph).
Within MotoLibrary's NSU archive, this model family spans 4 indexed model years from 1938 to 1941, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
