1957 Triumph TWN BDG125L

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Photo by Andy Saunders
Otto Hofmann's 1957 Triumph TWN BDG125L.

1957 Triumph TWN BDG125L
Claimed power:
6.7hp @ 5,200rpm
Top speed: 50mph
Engine: 123cc 2-stroke, air-cooled split-single
Weight (wet): 227lb (103kg)
Fuel capacity/MPG: 12ltr (3gal) / 100mpg (claimed)

Ever heard of a Triumph Cornet? Triumph Boss? Triumph Tessy? A 1957 Triumph TWN BDG125L? They’re all names of once-popular motorcycles (and one scooter), but unless your last name’s Schmidt, Schmiedeler or Schottenhauser, it’s doubtful any of these names ring a bell.

In the early 1950s, the German motorcycle market was among the world’s biggest, and it was crowded. In 1953, German factories produced 437,000 motorcycles, made by companies like Ardie, BMW, Zundapp, DKW, Maico, Victoria and Triumph Werke Nuremberg, or TWN.

The beginning
You’re probably asking yourself, “Wasn’t Triumph an English company?” The answer is yes, and no. The founder of Triumph was German-born Siegfried Bettman, who established the Triumph Cycle Company in 1886 in Coventry, England, to make bicycles.

Ten years later, in 1896, Bettman started the Orial Company in his native Nuremberg, Germany, which eventually became Deutsche Triumph Fahrradwerke AG, or the German Triumph Cycle Company. Production of motorcycles started in England in 1902, and the following year in Germany, with engines and other components shipped from Coventry. Although English sales were strong, German sales floundered, and production of motorcycles in Germany ceased in 1907.

Motorcycle production resumed following World War I, with the successful 275cc 2-stroke “Knirps” (meaning imp or knave), a close copy of the pre-war English 225cc Baby Triumph. The two now independent companies continued their association until 1930, with German Triumphs frequently using English Triumph engines.

To overcome confusion created by the close association, after 1930 English Triumphs were sold in Germany as TEC models (Triumph Engineering Coventry) while the German bikes used the Orial name for export. That is, until the French firm of the same name objected. After 1931, TWN (Triumph Werke Nuremberg) was used. At this time, imports of English Triumph engines ended.

TWN moves on
During the Thirties, TWN produced an extensive range and was fourth in sales in Germany behind DKW, Zundapp and NSU. The range included small 2-strokes and the mighty “RR” model: a 741cc V-twin side-valve with a Swiss MAG engine.

Technical chief Otto Reitz developed TWN’s BD250 split-single 2-stroke, using two pistons, two cylinders and a shared combustion chamber fed through a rotary inlet valve. The split-single idea was to open the exhaust ports before the transfer ports, thus encouraging gas flow into the cylinder without losing fresh charge through the exhaust.

During World War II, TWN produced thousands of BD250 2-stroke split-singles for the army. The factory built typewriters immediately after the war, and in 1948 started to produce motorcycles once again, all 2-strokes with an emphasis on economy.

Post-war TWN
In 1951 Otto Hofmann, then a 19-year-old journeyman mechanic, landed a job with DKW after the company moved its assembly lines from the Russian zone of Germany to Ingolstadt in American-occupied Bavaria.

The next five years were boom years for German motorcycle makers, but the very economic miracle they were helping to create eventually drove them out of business, as cars increasingly became affordable to everyone. But Otto remembers another factor: the weather. In the mid-1950s, Germany experienced several wet summers in a row, and soon even the enthusiasts were selling their motorcycles to buy tiny cars. “Nobody wanted to get wet all the time,” Otto says. “A friend changed from a BMW 600 to an Isetta. It had half the performance with the 250cc single-cylinder engine, but he got there dry!”

Post-war, TWN focused exclusively on 2-strokes, mostly split-singles. By 1956, the range had expanded to include the 50cc Fips moped, the 125cc Tessy and 200cc Contessa scooters, the BDG125, the BDG250SL with chrome-plated light alloy cylinders, the 350cc Boss with expansion-chamber-type exhausts, plus the Cornet, a 200cc split-single with 12-volt electric start. However, TWN’s two-wheeler sales, which had grown to 20,000 units in 1953, toppled to 2,000 in 1956.

The TWN factory, which had continued to build and refine its popular Triumph line of typewriters, was bought by radio and TV maker Max Grundig in 1953. In late 1956, Grundig discontinued motorcycle production in favor of telexes, typewriters and business machines.

Otto’s 1957 Triumph TWN BDG125L
In 1990 a friend tipped off Otto, now living in the U.S., about a bike he’d seen in Pittsburg, Calif. Otto called and found it was an old 1957 Triumph TWN BDG125L, not the DKW he’d been dreaming of. He said he’d think about it, and a few days later he went to view the bike.

What he found was a bike fresh out of the crate, and with an intriguing story. Apparently, the bike was shipped in 1956 to Cycle magazine publisher and would-be motorcycle manufacturer Floyd Clymer, who had expressed interest in marketing TWNs in the U.S. TWN likely hoped Clymer could sell its bikes in the growing American market, perhaps halting TWN’s downward spiral. Yet if true, it seems strange TWN would send its basic 125cc split-single model when it had a new, more modern 200cc model with electric start and a 350cc model with much more power. Then again, perhaps TWN sent one of each and this one was ignored, or maybe the crate and the cycle it contained were lost and never made it to Clymer. Whatever the case, the TWN BDG125L stayed in its crate in California for decades.

When Otto first saw the bike in 1990, the previous owner had removed the bike from its box but had been unable to make it run. The front fork had been removed for shipping, and the headlamp disconnected. It only took Otto a few minutes to re-wire the bike once he got it home, and with new gasoline and 20:1 oil mix, it started right up — even after 34 years in the crate.

When entries opened for the 2007 Legend of the Motorcycle event in Half Moon Bay, Calif., just a half-hour’s ride from his house, Otto offered the TWN for the 1930-1957 European class. After an agreeable day by the sea, he was surprised to come home with the class-winner trophy. “There were some wonderful bikes in the class, all of them bigger,” he says with obvious amazement at his TWN’s win. Perhaps, but there were none rarer or with a better story.

On the road
Otto was generous enough to offer a ride on the TWN, though not a long one. It has a mere 400 miles on the clock, and the more miles it accumulates, the less it’s worth. He trailered the bike to a deserted side road a few miles from Half Moon Bay and handed me the key.

The ignition switch, hidden behind a headlamp-mounted black plastic cover, will be familiar to any owner of a pre-1980s BMW. Insert the stilleto-like ignition key (similar to but a little more sophisticated than the nail BMW used until the 1970s) and turn once for ignition, twice for lights.

The bike starts easily (in my case, on the third kick of the left-mounted kickstarter), and after some blue 2-stroke smoke it settles into an easy, quiet idle. There’s a little more mechanical whirring due to the second piston, but the idle lacks the occasional misfiring of most piston-ported 2-strokes.

First gear selects with a gentle click and the clutch action is light. Acceleration is predictably slow, and opening the throttle once under way leads to more induction roar, but little more forward progress. Given that this is a 50-year-old engine that still hasn’t been broken in (the factory handbook calls for 30mph max for the first 1,000km), I’m not about to try for speed.

My caution is reinforced by misgivings about the tires — although they look brand new, the skinny 19-inch Metzelers are original equipment. Resigning yourself to leisurely proceedings is easy. Sit back on the softly sprung seat and watch the needle on the 2-inch VDO speedometer move slowly around the dial. The markings top out at a rather optimistic 80mph — a top speed of 50mph was mentioned in contemporary road tests. But the mph instead of kph markings on the speedometer show TWN was serious enough about the U.S. market to make some specification changes. The speedo is the only instrument, although there is a charging system warning light and a neutral light.

A closer look at the chassis reveals a forged headstock riveted to round tubes, which form a double-cradle frame. Tubes bolt together under the engine and under the seat nose, yet despite this low-tech construction the frame feels solid on the road.

The bike’s four gears are widely spaced, and progression uphill is moderate. Once headed downhill, the bike’s precise handling and solid feel are not easily unsettled by rough pavement, while the tiny drum brakes reveal themselves to work well enough, with easy lever action and good stopping power. One German magazine tester in the Fifties said they were the best ever: a sad commentary on braking technology of the time!

As for suspension, the rider is more aware of the movement afforded by the dual seat springs than the much more solidly sprung plunger suspension.

Paint is classic black, though red was available. Pinstripes provide relief, and there are bizarre and typically German touches, like rear hydraulic dampers equipped with dipsticks.

Practically perfect
Above all, this is a practical machine, a point underscored by the fully-enclosed chaincase to keep the chain clean and extend chain life. Riders expected these tiny 2-strokes to cover thousands of miles with only basic maintenance, which you could carry out with the tools in the tank-top tool bag. Opening that toolbox reveals the original tool roll, which includes a grease gun, handy for the zerk fittings found everywhere on the bike.

Otto says the only change he may make is to replace the dual seat — an extra-cost option at the time — with an original-equipment solo seat, if he can find one. Otherwise, the bike suits him just fine. Of course, he doesn’t plan to commute on it: he doesn’t need to do that any more. He’s retired, and his TWN125 retired before it ever started work. MC

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