Top 5 British bikes determined by expert Ian Falloon
1st - Velocette Thruxton
2nd - Vincent 1000cc V-twin
3rd - Triumph Bonneville
4th - Norton Commando
5th - BSA Rocket 3
If one bike typifies the ’60s it is undoubtedly Triumph’s Bonneville. By 1972 it was reckoned that 250,000 Bonnevilles had been built – at least three times as many as any comparable Norton or BSA twin.
The Bonnie also offered an unparalleled balance between looks and performance at a competitive price, plus a timeless appeal. "Precision, Power, and Performance," was the Triumph catchcry – there was no excess, and style followed function.
The Bonneville was conceived in the ’50s an era when many manufacturers coveted the title, ‘The World’s Fastest Motorcycle’. In 1955 Johnny Allen hit 193mph (311km/h) on his 650cc Triumph Streamliner at the Bonneville salt flats in Utah, but the record wasn’t recognised by the FIM due to a technicality.
This didn’t worry Triumph. In its eyes, and those of the US press, it still had the world’s fastest motorcycle. The following year, in 1956, Allen again returned to Bonneville, this time achieving 214mph (345km/h), but once more his record wasn’t accepted by the FIM. Again it didn’t matter, and from 1955 until 1970, except for a brief time when NSU held the record, Triumph could claim it as its own.
As all these records were obtained at Bonneville, Triumph boss Edward Turner decided to make the most of this association, and in 1959 the T120 Bonneville was released. It was intended to be the performance flagship, but initially was still very much a 650cc T110 Thunderbird hybrid. Performance was boosted through the use of a splayed-port alloy cylinder head, a higher compression and twin Amal monobloc carburettors without air filters. With 33.8kW (46hp) at 6500rpm, the Bonneville was claimed to be the fastest production bike available – a claim substantiated in 1961 when the British motorcycle press tested a T120R at 117mph (188km/h).
The first unit construction Bonneville appeared in 1963 and at first wasn’t as highly rated as the pre-unit predecessors. While there were gains in the frame, which reverted back to the classic Triumph single downtube, the unit-construction engine lost out in smoothness and electrical reliability. However, where the new T120 really scored over the pre-unit 650s was in its compact format and weight. At 165kg it was nearly 14kg lighter, and this contributed to much brisker on-the-road performance. Every year saw a range of detail improvements, the 1968 to 1970 versions considered the finest.
Even after a decade the Bonneville was still a force in production racing, Malcolm Uphill riding to a record-breaking 100mph (160km/h) win in the 1969 Production TT at the Isle of Man. A standing-start lap of 100.9mph (162.4km/h) saw the first ever 100mph lap by a production machine, this contributing much to the Bonneville legend. The oil-in-the-frame model appeared in 1971 and the engine grew to 750cc in 1973. The final Meriden Bonneville was the T140E of 1983.
Affectionately known as the ‘Bonnie’, the T120 was relatively powerful, good looking, and the leading performance motorcycle of the 1960s. It was simply the finest large-capacity sporting motorcycle available at the time.