Triumph Speed Twin 500
Triumph Speed Twin 500 | |
Manufacturer | |
---|---|
Production | 1938 - 46 |
Engine | Four stroke, parallel twin, OHV |
Compression ratio | 7.1:1 |
Ignition | 6 V, magnetic flywheel |
Transmission | 4 Speed |
Frame | Singe tube frame |
Suspension | Front: Rigid fork with leaf spring Rear: Rigid, spring loaded saddle |
Brakes | Front: Drum Rear: Drum |
Front Tire | 3.25 - 19 |
Rear Tire | 3.50 - 19 |
Weight | 182 kg / 401 lbs (dry), |
Fuel Capacity | 18 L / 4.8 US gal / 4.0 Imp gal |
Manuals | Service Manual |
Engine[edit | edit source]
The engine was a Air cooled cooled Four stroke, parallel twin, OHV. The engine featured a 7.1:1 compression ratio.
Drive[edit | edit source]
Power was moderated via the Wet, 6 plate.
Chassis[edit | edit source]
It came with a 3.25 - 19 front tire and a 3.50 - 19 rear tire. Stopping was achieved via Drum in the front and a Drum in the rear. The front suspension was a Rigid fork with leaf spring while the rear was equipped with a Rigid, spring loaded saddle. The Speed Twin 500 was fitted with a 18 L / 4.8 US gal / 4.0 Imp gal fuel tank. The bike weighed just 182 kg / 401 lbs.
Photos[edit | edit source]
Overview[edit | edit source]
Triumph Speed Twin 500
THIS BURGUNDY BEAUTY MAY look like a motorcycle,
but to the people who first clamped eyes on it when it was introduced back
in 1937, it looked more like a new beginning.
To Edward Turner, that human bundle of enthusiasm and impatience who was
Triumph's managing director and chief designer, it was a fast, smooth Twin that
looked like a Single. It was the machine to lure British riders away from their
beloved and trusted Thumpers, and onto multi-cylindered bikes.
To the riding public, who first saw the all-new 1938 Triumph Speed Twin at
Britain's Olympia Show in late 1937, it oozed style and sophistication, and it
promised performance, all in a package that was well-constructed, light and as
lean as a whippet.
Today, it still looks right. It is the progenitor
of the fabulous Triumph Bonneville-even, one could argue, the progenitor of the
1991 line of modern Triumph motorcycles. It was the Japanese in the 1960s who
adopted the notion that for any given displacement, more pistons, spinning more
quickly, would produce more power, more smoothly, but this Triumph is the
product of the same sort of thinking.
Triumph was an old-line firm, founded in Coventry as a bicycle manufacturer by a
pair of German immigrants in 1897. The firm's first motorcycle, essentially a
bicycle powered by a clip-on Minerva engine, was produced in 1902.
For a time, J.A.P. and Fafnir engines also were
employed, but by 1903, the firm was designing its own engines. A Triumph powered
by one of those engines recorded a win at the Isle of Man TT as early as 1908.
By 1913, Triumph's engineers were experimenting with a 600cc vertical-Twin, but
when Europe erupted in war in August. 1914, development ceased. After the war,
the company stuck with Singles in both side-valve and ohv configurations. A
633cc vertical-Twin-powered machine was produced in 1933, but was stodgy in
appearance and failed to generate buyer enthusiasm. It quietly disappeared.
That's when Turner entered the picture. Triumph,
beset by severe financial difficulties, was taken over by new owners in 1936,
and Turner was installed at the top of the company's hierarchy. He, and with
him, the company, went from strength to strength. The first of those strengths
was the 1938 Speed Twin, which, quite literally, turned the company around. The
bike you see here, a 1947 model, is, with the exception of its post-war
telescopic fork and 19-inch front wheel, basically identical to the 1938 model
that, like all pre-war Speed Twins, used a girder fork and a 20-inch front
wheel.
Triumph lore has it that Turner cribbed the
design of the Speed Twin's engine from that of the Riley Nine automobile, an
example of which he owned. Wherever the design came from, the Triumph appeared
with a 63mm bore and 80mm stroke yielding 498cc of displacement. Its cylinder
head was cast iron, and its compression ratio was 7:1. It breathed through a
single Amal carb with a minuscule throat opening. Ah, but the engine was smooth,
and it produced 28 horsepower-four more than a Single of
comparable size. Depending upon which road test you read, and upon how much
tailwind assistance the bike received, this first Speed Twin was capable of
between 94 and 107 miles per hour. Average fuel consumption of 65 mpg was
claimed.
These figures satisfied an enthusiastic public. The Speed Twin prospered, and
production of bikes carrying that model name continued through 1966. In all,
nearly 45,000 examples were built, helping to establish Triumph as the world's
most prestigious motorcycle manufacturer.
The bike you see here was bought last year by
Beverly Hills architect Lucian T. Hood for $5000, and was recently restored by
the Time Machine Motorcycle Works in Costa Mesa, California. The bike was
acquired from its second owner in fairly original shape, missing a few bits and
pieces and showing 21,263 miles on its odometer. Its value now, polished and
perfect, right down to the brass Terry tag on the rear of its saddle, is
approximately $15,000.
How original is it?. Well, its pistons are 7.8:1
units from a Tiger 100, its rear fender stays are handmade replacements, its
leather seat cover is a custom item, and the aluminum cam plate in its
transmission has been replaced by a more durable steel plate. But the rest of
it? Well, take a look. And if. in looking, you feel transported back to the days
when men were men and streetbikes were kick-started, you're on the right track.
This kind of simplicity, design excellence and quality of assembly are the
elements that assigned Triumph Twins their legendary status.
And if the new line of Triumphs marks another new beginning, another chance at
legend, there is every reason to argue that it has this previous new beginning
to thank for the opportunity.
Source Cycele 1984
Make Model | Triumph Speed Twin 500 |
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Year | 1938 - 46 |
Engine Type | Four stroke, parallel twin, OHV |
Displacement | 498 cc / 30.4 cub in. |
Bore X Stroke | 63 x 80 mm |
Compression | 7.1:1 |
Cooling System | Air cooled |
Induction | Single Amal carburetor |
Ignition | 6 V, magnetic flywheel |
Starting | Kick |
Max Power | 20.9 kW / 28 hp @ 6000 rpm |
Clutch | Wet, 6 plate |
Transmission | 4 Speed |
Final Drive | Chain |
Frame | Singe tube frame |
Front Suspension | Rigid fork with leaf spring |
Rear Suspension | Rigid, spring loaded saddle |
Front Brakes | Drum |
Rear Brakes | Drum |
Front Tire | 3.25 - 19 |
Rear Tire | 3.50 - 19 |
Dry Weight | 182 kg / 401 lbs |
Fuel Capacity | 18 L / 4.8 US gal / 4.0 Imp gal |