Although often recognized immediately for cars like the Prinze and ground-breaking Ro 80, NSU was, at one stage, the world’s largest producer of motorcycles. However, some models are rarer than others. Such is the case with the 1932 NSU 501 OS. The company only produced 2,183 examples of that model, and they don’t often appear on the classic market. That means the listing of this one here on eBay represents a chance for someone to secure a slice of automotive history that isn’t seen every day. It is located in Redwood City, California, with bidding racing past to reserve to sit at $10,350.

NSU’s four-wheel history has seen its motorcycle exploits ignored by many, which is surprising. At one point during its history, it was the world’s largest producer of motorcycles. This 501 OS rolled out of the factory in 1932 and has been in the seller’s possession for five years. They planned a faithful restoration, but circumstances meant the project stalled before it could start. They admit it is missing some minor parts but don’t elaborate on what they might be. I can confirm the lids for the pannier boxes are gone, leaving the successful bidder to perform detective work to locate replacements. It retains components like its correct “fishtail” exhaust and the rubber knee-guards on the tank. It is a prime candidate for a cosmetic restoration and would look stunning with a fresh coat of its original Red paint. However, if the buyer chose the preservation route, it would still turn heads. The frame looks good, while the fenders and tank have no appreciable dents or marks. Some plated components would require professional attention as part of a high-end build. Still, the overall impression is that returning this beauty to its former glory should be relatively straightforward.

In 1929, the company scored a coup by luring designer Walter Moore from Norton, setting him to work producing a new motor to power its machinery. The fruit of his labor was its single-cylinder OHV “OS” Series engine, which was introduced in 1932 and served faithfully for most of that decade. It, unsurprisingly, shared many similarities with Norton engines from that era, with both featuring a distinctive “lumpy” engine note courtesy of a relatively aggressive camshaft grind. This NSU features the 494cc version that produces 11hp. The transmission is a gray area, with some resources suggesting it should be a three-speed and others specifying a four-speed unit. It isn’t a jet on wheels but should cruise happily at around 50mph on the open road. The seller says the engine ran when they purchased it, but whether that is still true is unclear. These are robust powerplants, so coaxing this one to life may not be challenging. Simple engineering means that basic servicing and maintenance could see it return to active service relatively quickly.

That NSU remains largely forgotten as a motorcycle manufacturer is an injustice. The brand achieved notable success on the racing circuit, including wins at the legendary Isle of Man TT. It also produced a successful motorscooter, the Quick. The company sold more than 250,000 of those little devices between 1936 and 1953, allowing people to gain mobility during the late Depression and post-war years. The 1932 501 OS is a rarer beast and deserves to return to active service. Its new owner will unlikely be confronted with an identical machine at a show or meeting. Locating parts may seem daunting, but a worldwide owner’s club network is often a resource where the buyer could strike gold. This beauty has generated considerable interest since being listed, attracting thirty-five bids at the time of writing. If an unusual classic motorcycle has been on your radar, would you consider joining the bidding war on this beauty?