D-Rad
On the western edge of Berlin, in Spandau, there's a stretch of industrial ground that once made munitions for the Kaiser's army. After 1918, with the Treaty of Versailles forbidding that trade outright, the men running Deutsche Industriewerke AG had a factory built for war and nothing left to build. What they did next is the whole story of D-Rad in miniature: a heavy-industry firm with no obvious business making motorcycles decided to make motorcycles anyway, and for a decade and a half they made some of the sturdiest, most sensible machines to come out of Weimar Germany.
Origins in Spandau
Deutsche Industriewerke itself dated back to 1896, a Berlin-Spandau concern that had grown up around metalworking and armaments long before anyone there thought about two wheels. The postwar reckoning forced a pivot, and by 1920 the Spandau works had begun turning out motorcycles under two names, Star and Derad, using a 392cc horizontally opposed twin engineered by H.F. Günther. Sales literature from the period even traces production back to 1919, which puts the real starting point of the marque a few years earlier than the corporate paperwork suggests. The formal identity most collectors know today didn't arrive until 1923, when Deutsche Industrie-Werke took full control of the operation and renamed it D-Rad — shorthand for "Deutsches Motorrad," German Motorcycle, about as plain and unpretentious a name as a marque could choose. That plainness suited the machines. Most sources put the start of actual motorcycle production at 1919–1920 under the Star name, well before the D-Rad badge existed; a commonly cited 1921 date appears to refer instead to the founding of Deutsche Kraftfahrzeugwerke AG, a related corporate entity, rather than to the bikes themselves. So it's fairer to say D-Rad's motorcycle story runs from around 1919–1920 through the name change in 1923 and beyond, rather than pin it to a single clean year.
The early machines
The Star-badged twin was the foundation, a boxer engine of modest displacement that prized durability over speed, and it set the tone for everything Spandau built afterward. The M23, introduced under the new D-Rad name, refined the formula with better cooling and detail changes, though it remained visually close to its Star ancestor. The M24 followed in 1924, another round of incremental improvement on the same 392cc IOE flat-twin layout. These were not exciting motorcycles in the way a racing single might be exciting; they were built to survive German roads and German winters, and riders of the day nicknamed them "Springboks from Spandau," a phrase that stuck because it captured something true about the bikes' character — tough, a little agricultural, built to take a hit and keep running.
1925 marked a real turning point. D-Rad had dabbled in automobile production alongside motorcycles, but that year the company dropped cars entirely and committed itself to two wheels. The R 0/4 and R 1/4 arrived as the first fruits of that focus, both built around a 496cc side-valve engine, with the R 1/4 pitched as the sportier of the pair. The R 0/4 in particular became a genuine backbone model for the company, with something on the order of 25,500 built over its run — a serious number for a manufacturer that had only been building motorcycles under its own name for a couple of years.
The Stolle era and the defining machines
The engineering direction of D-Rad changed hands in 1927, when Martin Stolle arrived from BMW to replace Max Christiansen, the designer who had shaped the marque's machines up to that point. Stolle's arrival matters because it's the hinge on which D-Rad's most interesting decade turns. He brought a new engine design into production by 1929, and the following year the company put out the R 10 — a genuinely modern motorcycle for its era, with a trapeze front fork, a saddle tank instead of the older flat-sided tank shape, and a new overhead-valve engine in place of the side-valve units that had carried D-Rad through the 1920s. At 496cc and roughly 20 horsepower, the R 10 was the sportiest and most technically ambitious machine Spandau ever put its name on, though only around 3,500 were built before the company's fortunes turned.
Alongside the R 10, D-Rad kept a range of side-valve models in production through the turn of the decade: the R 0/6, the R 9, and the R 11, all built around the same 496cc architecture at different states of tune, and all sold in reasonably serious numbers — the R 0/6 at around 9,000 units, the R 9 at roughly 10,000, the R 11 at about 2,500. There was also a small two-stroke, the R 20, using a 200cc Bark-built engine, of which around 2,000 were made, aimed at riders who wanted something lighter and cheaper than the flat-twin and side-valve singles that made up the rest of the range.
D-Rad also built a commercial variant worth remembering: the L 7, a three-wheeled delivery vehicle based on the R 0/4 running gear, with a load box mounted up front and a tandem two-seat arrangement for the rider and a passenger behind. It was introduced in 1927 and, by most accounts, stayed in production into 1930, though there's also a suggestion that true series production of the L 7 didn't begin until 1929 even though the design dates from a couple of years earlier — meaning the 1927 date may mark the introduction of the design rather than the start of full-scale manufacture. Whatever the precise bracket, it's a reminder that D-Rad wasn't only chasing sporting riders; the company built its own sidecars too, and D-Rad-powered sidecar taxis worked the streets of several German cities during this period, which says something about how the marque was regarded at street level — not as an exotic name, but as reliable working machinery.
Racing
D-Rad's competition record is harder to pin down than its production numbers. The machines developed under Stolle's direction in the early 1930s are consistently linked, across several sources, to a group of riders — Franz Heck, Franz Seelos, Max Polster, and Paul Bülow — whose names turn up again and again in connection with the marque, though no source lays out which events they entered, which years they rode, or what they actually won. So it's best to take the connection between D-Rad and these four riders as established by repetition across sources, but to treat any claim of specific championships or race results as unproven. What can be said with more confidence is that Stolle's OHV engine and the R 10's chassis were built with sporting use in mind, and that D-Rad clearly wanted a foothold in competition during its final, most technically capable years — even if the exact scoreboard hasn't survived in any source worth trusting.
Collapse and the NSU takeover
By the early 1930s the same forces reshaping the rest of German industry caught up with Spandau. The worldwide financial crisis hit motorcycle sales hard, and D-Rad, despite the technical strength of machines like the R 10, couldn't outrun the collapse in demand. NSU bought the company in 1932, taking on D-Rad's operations along with a reported 1,700 complete, unsold motorcycles still sitting in inventory — a fairly blunt indicator of how badly the market had turned. Production wound down that same year, and by most accounts the last D-Rad-badged motorcycles left the Spandau works in 1933, after which the name disappeared from NSU's lineup entirely.
Total production across the marque's life is disputed. One frequently cited figure puts the number at around 44,500 machines, while another source puts it closer to 60,000 built between 1922 and August 1932. The gap between those two figures is wide enough — something on the order of 35 percent — that neither should be treated as settled fact; readers researching a specific D-Rad model or trying to gauge rarity should know the total production count is genuinely disputed rather than precisely known.
What's left of D-Rad
The name never came back. There was no postwar revival, no small workshop reviving the badge for a limited run of retro-styled twins, nothing of the kind. D-Rad belongs entirely to Weimar-era Germany, a marque that lived and died within about a decade and a half, absorbed into NSU and then folded away as NSU pursued its own, much longer history.
What survives is scattered through German collections and the occasional continental auction: R 0/4s and R 9s in varying states of restoration, the odd R 10 with its OHV engine and trapeze fork intact, and further down the rarity scale, a handful of L 7 delivery three-wheelers that turn up as curiosities more than as riders. None of it is common. D-Rad was never a mass-export brand in the way some of its German contemporaries became, and the machines that exist today are mostly the ones that stayed in Germany from the start. For collectors of 1920s and early 1930s German motorcycles, a genuine D-Rad — solidly built, unglamorous in the best sense, carrying the Springboks-from-Spandau reputation earned when the factory was still finding its feet after a war it had nothing to do with — remains one of the more honest artifacts of that era to own.