1955 Douglas Dragonfly
By Roland Brown
1955 Douglas Dragonfly
Years produced: 1955-1957
Total production: 1,500 (approx.)
Claimed power: 17hp @ 5,500rpm
Top speed: 70mph (approx.)
Engine type: 348cc overhead valve, air-cooled opposed twin
Weight: (dry) 165.6kg (365lb)
Price then: NA
Price now: $5,000-$8,000
MPG: 55mpg (est.)
Cruising along with the speedo in its big nacelle reading about 50mph, the elderly 1955 Douglas Dragonfly felt so smooth and stable I couldn’t help being impressed. For a bike built just more than half a century ago, the 350cc flat twin seemed like a sophisticated and efficient machine that must surely have been an excellent all-rounder back in the mid-Fifties.
The Dragonfly was comfortable, too, thanks to a roomy riding position and reasonably good suspension. And I’m sure I can’t be the only one who finds its look curiously attractive, especially the distinctive way the nacelle leads into the large, rounded gas tank.
But while my impression of the Douglas Dragonfly was positive, that wasn’t how most motorcyclists regarded the bike back in 1955. Instead of being a big success, the Dragonfly sold so slowly following its introduction that Douglas — which had built its first motorcycle back in 1907 and had won the Junior TT as long ago as 1912 — was taken over in 1956, and ceased bike production altogether a year later.
Good, but not great
Such a hasty demise doesn’t reflect well on the Douglas Dragonfly, and perhaps the bike’s weakness was exposed when, shortly after my ride, I sat down to make some notes — and had trouble remembering very much about the experience. Smoothness and efficiency are all very well in a motorcycle, after all, but plenty of rival bikes provided a lot more performance and excitement than the Douglas Dragonfly.
It would be wrong to blame the Dragonfly for causing the end of Douglas motorcycles, because the Bristol firm had been struggling for years. Its high point had arguably come in 1923, with victories in both the Senior and Sidecar TTs, the latter with an innovative leaning outfit piloted by Freddie Dixon. But Douglas later suffered a string of financial collapses, notably in 1937 following the deaths of founding members William Douglas and his son, John.
Despite that setback, Douglas was reasonably successful during World War II, gaining work with trucks, aircraft parts and generators. The firm had always been versatile, having built cars and tractors, among other things, in its early days. After World War II, Douglas recommenced bike production with a new model called the Douglas T35, whose 348cc flat-twin engine was based on the generator — not the most promising heritage! The twin-downtube frame was developed from that of the Endeavour, which had been Douglas’ first flat twin with BMW-style transverse cylinders when launched in 1934.
The T35 stood out when launched in 1947, because most rival British bikes were simple rigid-framed singles. By comparison, designer George Halliday’s machine seemed relatively sophisticated, despite its engine’s humble origins. As well as its twin-cylinder engine, Douglas motorcycles featured a patented torsion bar (twisting metal rods instead of coil springs) suspension system at both ends. But the T35 suffered with a number of problems. Various minor design flaws, poor quality control and use of sub-standard materials combined to give Douglas motorcycles a reputation for poor reliability.
The T35 was improved over the years, being produced in a series of updated versions, beginning with the MkII and ending with the MkV. But Douglas was in a worse financial position than ever by the time the MkIII model was launched in 1948, and the firm went into receivership later that year. Although production continued, expenditure was severely restricted and there was little chance of a full recovery.
Some racing and development work continued, under the control of former race ace Freddie Dixon. In 1950, the firm introduced two sporty versions of the T35, the 80 Plus and 90 Plus, named after their claimed top speeds of 80mph and 90mph, respectively. Engine changes for both included new cylinder heads, extra cooling fins and a strengthened crankshaft. In addition, the 90 Plus had a higher compression ratio, and each engine was dyno-tested to confirm it produced at least 25hp. The 90 Plus just about lived up to its name, which meant it performed pretty well, but Douglas motorcycles continued to struggle in the early 1950s.
Hopes were boosted in 1954 with the unveiling of the Dragonfly, which combined a new chassis with a modified version of the 348cc engine. When launched at the Earl’s Court motorcycle show in London, the model made quite an impact, largely due to its striking styling. The sheet steel nacelle held the 80mph speedo, a smaller ammeter and the ignition switch, as well as the headlamp.
The new engine retained the traditional T35 capacity of 348cc from near-square dimensions of 60.8mm by 60mm bore and stroke, but was influenced both by the 90 Plus and a 500cc prototype that had been developed and then abandoned a few years earlier. The Dragonfly’s cylinder heads were based on those of the 500, while the bottom end was strengthened in 90 Plus style with stronger crankcase webs and an upgraded lubrication system.
Like the T35, the Douglas Dragonfly used chain final drive rather than a BMW-style shaft. Because the crankshaft was in line with the bike, this required a bevel-gear system between the four-speed gearbox and the front sprocket, to turn the drive through 90 degrees. The rectifier and coil were located under the large gas tank; other electrical components lived on top of the engine, under an aluminum plate that helped give the engine a notably smooth look.
Chassis specialist Reynolds built the twin-downtube frame and the front suspension, which employed the pivoted, twin-shock system designed by Ernie Earles, who also styled the Dragonfly’s nacelle. At the rear, twin shocks replaced Douglas’ previous torsion bar suspension system, and were considered a sophisticated feature at the time. At 365lb dry the Dragonfly was slightly heavier than the T35 MkV, but was respectably light given its sturdy chassis.
On the road
This bike, a very clean and nicely restored 1955 model, felt reasonably light once I’d managed to haul it off its rather stubborn center-stand. The way the nacelle remained in position when I turned the bars seemed strange at first, but in most respects the Douglas was normal and well behaved. Its engine started easily enough, given a fairly light kick of the starter lever, and didn’t seem particularly noisy despite the model’s reputation for rattling.
That was an indication that this recently rebuilt engine was in good condition, and the Douglas ran well throughout my test. There was a fair bit of noise when I got under way, though it was a not-particularly-pleasant whining sound from the engine, which largely drowned out the restrained note from the Dragonfly’s dual mufflers. At least the flat twin was impressively smooth.
Given that the Dragonfly produces only 17hp, I shouldn’t have been surprised that its performance was less than dramatic. Acceleration away from a standstill was labored, even when the engine was revved reasonably hard (there was no tachometer to check). And although its single Amal carb gave reasonably crisp low-rev response that made slow-speed maneuvering easy, the bike didn’t have much low-rev punch. At least it cruised comfortably at 50mph or slightly more, aided by the roomy, big-bike feel provided by the riding position.
Perhaps it was unfair to have expected much more, because this was after all only a 350cc twin. It seems strange, however, that the new flagship should be notably slower than its T35 predecessor. In its defense, the bike cruises smoothly and pleasantly between 50 and 60mph on a flat road, feeling as though it would happily do so until its big 24ltr (6.5gal) tank ran dry. Its four-speed gearbox worked well, too, and was apparently a big improvement on the previous transmission. Top speed was just over 70mph, but given this bike’s age and fairly recent rebuild, I didn’t try to reach that.
There wasn’t much wrong with the Dragonfly’s chassis, at least by the standards of 1955. At a time when most bikes had crude telescopic forks and plunger rear suspension, the Douglas’ layout of Earles fork front and twin shock rear end was advanced for any bike, let alone a middleweight. The ride is reasonably firm and well controlled, and the Douglas steers with a nicely neutral feel and is very stable, even over bumps.
The Dragonfly’s brakes were heavily criticized in a 1955 Motor Cycling road test, but this bike’s stoppers were no worse than I’d expected of the typical period use of single-leading-shoe drums at each end. The front drum needed a firm squeeze of the lever, but didn’t give any drama. And there was no faulting the grip from the Dragonfly’s Avon Roadrunners, better rubber than would have been available when the bike was new.
Unfortunately for Douglas, the Dragonfly tended to spend far too long on the showroom floor after the model belatedly reached the dealers in 1955, nine months after its Earl’s Court introduction. That lukewarm first magazine road test, plus the bike’s modest performance, relatively high price and Douglas’s reputation for mixed reliability and quality control, ensured that the model wasn’t the success the Bristol firm so badly needed.
In 1956, Douglas was taken over by a firm called the Westinghouse Brake & Signal Company. Motorcycle production was abandoned in the following spring, after about 1,500 units had been built. The final batch was sold at cut-rate prices by south London dealer Pride & Clarke. Another of the British motorcycle industry’s best-known marques was gone. MC
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