NSU 351 OSL 1937 - Specifications & Review

Introducing the 1937 NSU 351 OSL Motorcycle

The 1937 NSU 351 OSL stands as a remarkable testament to the golden age of motorcycle engineering, perfectly positioned within the sport category for enthusiasts seeking a blend of performance and classic style. Launched during a period when motorcycle design was evolving rapidly, the 351 OSL was developed by NSU, a pioneer in two-wheeled innovation. With its sleek lines and robust build, this motorcycle not only captured the spirit of the era but also attracted riders who craved both speed and agility on the open road.

Engine Performance and Riding Characteristics

At the heart of the NSU 351 OSL lies a spirited single-cylinder, four-stroke engine with a displacement of 346cc. Producing an impressive 18 HP at 5020 RPM, it propels the motorcycle to a top speed of 110 km/h (68.4 mph), making it a formidable contender in its class. The engine’s bore and stroke dimensions of 75.0 x 79.0 mm allow for a smooth power delivery and a thrilling riding experience. Riders will appreciate the responsiveness of the Graetzin KE 25/43 carburettor, which ensures a consistent fuel supply, while the air-cooling system keeps the engine at optimal operating temperatures. The 4-speed gearbox, paired with a chain final drive, provides a seamless transition through gears, enhancing the overall riding dynamics and making it a joy to navigate both urban streets and winding country roads.

Key Features and Technology

The NSU 351 OSL is built on an open double steel frame, offering a balance of strength and lightweight handling, weighing in at just 110 kg (242.5 pounds). This motorcycle is equipped with expanding drum brakes at both the front and rear, ensuring reliable stopping power, a crucial feature for any sport bike. The dimensions—length of 2020 mm, width of 770 mm, and height of 940 mm—create a compact yet comfortable rider triangle, allowing for an engaging and confident ride. Additionally, the kickstarter is a nod to the era's charm, inviting riders to embrace the classic experience of starting their bike the old-fashioned way.

Pros and Cons of the 1937 NSU 351 OSL

Pros:

1. Classic Aesthetics: The NSU 351 OSL boasts vintage styling that appeals to collectors and enthusiasts alike, making it a standout piece in any motorcycle collection.
2. Responsive Performance: With a lightweight design and peppy engine, this motorcycle offers an exhilarating ride, perfect for both new riders and seasoned enthusiasts.
3. Reliable Engineering: Built with quality materials and craftsmanship, the 351 OSL exemplifies durability and longevity, a hallmark of NSU's reputation.

Cons:

1. Limited Power: While its 18 HP is respectable for its time, modern riders may find it underpowered compared to contemporary motorcycles.
2. Drum Brakes Limitations: The drum brake system, while adequate for the time, may not provide the same stopping power and feedback as modern disc brakes.
3. Kickstarter Only: The absence of an electric starter may deter some riders who prefer the convenience of modern ignition systems.

In summary, the 1937 NSU 351 OSL is more than just a motorcycle; it’s a slice of history that encapsulates the spirit of an era defined by innovation and adventure. Whether you're a collector or a rider with a passion for the classics, this motorcycle promises a ride steeped in nostalgia and performance.