2021 Shannons Winter Timed Online Auction
1951 Triumph Thunderbird 650cc Motorcycle
|Engine||649cc OHV twin-cylinder|
This lot is no longer available
Popularised by Marlon Brando’s appearance in the 1953 movie ‘The Wild One’, the Thunderbird was based on Triumph’s classic Speed Twin and could rightfully claim to be the most powerful parallel twin available on the market at the time of its launch in 1949. The original 6T Thunderbird saw Edward Turner’s twin bored from 500cc to 650cc, producing 34 horsepower. To counter criticism from Americans who complained that the new model offered no real performance advantage over the Speed Twin, Triumph increased the carburettor size and raised the compression ratio from 7:1 to 8:1, plus added chrome to jazz up the appearance. Triumph arranged for a series of high-speed demonstrations at the famous banked Montlhéry circuit near Paris to help promote their latest product, covering 800 kilometres at an incredible average of more than 145 km/h. Indeed, the 650cc engine successfully held the world speed record for motorcycles between 1955 and 1970, set on the dry lakes at Bonneville, and much of the model’s success can be attributed to the American desire for more cubic inches and horsepower. The Thunderbird had such an abundance of power and torque that the bike was capable of cruising at more than 150 km/h without fuss – perfect for the long, straight roads of countries like America and Australia, where it proved popular with local police forces in the early 1950s. Without doubt one of the all-time classics, the Triumph Thunderbird is a truly rewarding motorcycle to own and the opportunity to acquire one is all too rare.