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Derived from the Terrier, the Tiger Cub came into the post-war world in 1954. Not merely a sports version of the 150, the 199cc Triumph obtained much of its extra speed from its extra capacity. An inclined overhead-valve single with unit construction for a four-speed gearbox driven by a non-adjustable chain, the Cub had an oval timing-side casting and a very neat appearance. It was equipped at first with plunger rear springing, later with pivot-fork type. An excellent performer, top speed was 68mph and with plenty of acceleration, it could outpace most two strokes of comparable size.
Triumph on-or-off road bike, the Trophy was first listed in 1949. A combination of the Tiger 100 and Grand Prix detuned to one carburettor, and running on a compression ratio of 6:1, the engine was carried in a specially shortened high-clearance frame with a siamesed exhaust system tucked above the primary case and ending in a lightweight silencer. Light and manoeuvrable, the Trophy was equipped with a detachable lighting set making it a practical all-rounder for everyday use and weekend sport.
Born out of demand from mainly their American customers, Triumph enlarged the Speed Twin in 1946 by 150cc and called it the Thunderbird. Both bore and stroke increased from 63 x 80mm to a nearer "Square" dimension of 71 x 82mm, giving 649cc and a power output of 34bhp @6300rpm. The 8hp advantage over the 500 produced a noticeable surge of mid-range torque and a road performance superior to the Tiger 100.
The Triumph Speed Twin was probably the best known motor cycle of the immediate post-war period. Strikingly good looking and built to a high standard, it was chosen as the mount for the London Police. A vertical-twin layout, it featured an all-iron block and head. Light and simple, the engine was virtually a single with two pistons travelling in unison to give even firing intervals and impelled by a 360 degree crankshaft. over output was approximately 25bhp at 5500rpm, which was enough to power the bike at up to 85mph.
