Triumph's pre-unit twin-cyclinder motorcycles were produced from 1938 to 1962, with engine sizes of 350cc, 500cc and 650cc. Ridden both on the road and in competition , the bikes formed the basis for Triumph's success through the 1940s to the 1960s. With iconic names such as Speed Twin, Tiger 100, Trophy and Bonneville, the pre-unit Triumphs came as sports bikes and tourers. With their superb styling and reliable engines, there were a favourite both at home and abroad.
Matthew Vale started his motorcycling career in 1974 at the age of sixteen with a NSU Quickly moped. He continued riding for a further ten years, culminating with the ownership of a Triumph T140E Bonneville. He bought his first restoration project, a 1970 Triumph Bonneville, in 1998 and started writing books and articles about classic bikes in the early part of the new millennium. This is his sixth book for Crowood.