Long live the vertical twin!

Triumph’s massive belt-drive 270-degree crank Thunderbird twin was clearly aimed at the American market. The original capacity of 1597cc was later raised to 1699cc.

With its instant torque, the vertical twin type of engine that powered Triumph’s Speed Twin success in the late 1930s postwar years is still exciting motorcycle enthusiasts today.

Let’s see how things developed from the 1960s to 2015.

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The Norton Commando, introduced in 1967, was a British Norton Villiers motorcycle with an overhead-valve parallel twin engine, based on Bert Hopwood’s original 1953 500cc Model 7 twin.

Its capacity was increased progressively to the 750cc of the Atlas, a powerful road-burner that suffered from uncomfortable vibration, but the Commando changed all that.

Read more in November’s edition of OBM
 

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