TRIUMPH SPEED TWIN

TRIUMPH SPEED TWIN

TRIUMPH SPEED TWIN

Motorcycling was changed for ever when the Speed Twin burst onto the scene in 1937, dramatically proving that two cylinders could be better than one, and triggering an era of parallel twin dominance that would last for more than three decades. It's doubtful whether any British bike has had more influence on those that followed.

The Speed Twin's appeal was easy to understand. Triumph boss Edward Turner's 498cc masterpiece was fast, stylish, practical and reasonably priced, with a distinct performance advantage over the majority of single-cylinder machines that had dominated motorcycle production until then.

Turner himself, rarely reluctant to express an opinion, was in no doubt about a twin's attributes.

'A twin gives better torque,' he said. 'It will run at higher revolutions than a single of similar capacity without unduly stressing major components.

Because the firing intervals are equal, which means even torque, the low-speed pulling is better. The engine gives faster acceleration, is more durable, is easier to silence and is better cooled. In every way it is a more agreeable engine to handle.'

TRIUMPH SPEED TWIN

Effortless cruising

TRIUMPH SPEED TWIN

Most riders found it hard to disagree after riding the Speed Twin, which was matched by some singles in its top speed of just over 90mph (145km/h), but not in the relatively smooth and effortless way it would cruise at more than 70mph (113km/h). The TRIUMPH SPEED TWIN pushrod-operated engine, which had a 360-degree firing arrangement (pistons rising and falling together), was quite softly tuned, with a 7:1 compression ratio and a maximum output of 29bhp at 6000rpm. Although there was some vibration, by single standards it was smooth.

Turner had recently arrived from Ariel (where he had designed the Square Four), after that firm had taken over Triumph. He had announced himself by revamping Triumph's range of 500, 350 and 250cc singles, boosting sales with fresh styling and catchy new names: Tiger 90, 80 and 70.

Turner's rare talent for both marketing and styling were again evident in the Speed Twin, with its evocative name and handsome lines.

TRIUMPH SPEED TWIN

Handling rated highly

TRIUMPH SPEED TWIN

The Twin's lean, simple look was not misleading. It used essentially the same frame and forks as the Tiger 90, was actually slightly lighter than the 500 single, and its engine was slightly narrower. The drum brakes were powerful and handling was rated highly, although the rigid rear end tended to hop over bumps.

It was the engine, though, that sent the testers of the day into rapture. 'On the open road the machine was utterly delightful,' reported The Motor Cycle. 'Ample power was always available at a turn of the twist-grip, and the lack of noise when the machine was cruising in the seventies was almost uncanny.' The magazine managed a .two- way average of 93.7mph (f51km/h) and a 'truly amazing' one-way best of 107mph (172km/h).

Predictably, given all this and the Triumph Speed Twin competitive price of little more than the Tiger 90, the bike was a huge success. The outbreak of the Second World War put a halt to development, but by 1948, three year's after war's end, all the main manufacturers had parallel twins of their own. Meanwhile the Speed Twin had been tuned to create a sports model, the Tiger 100, and a 650cc derivative was also being developed. Triumph's parallel twin revolution was well under way.