By Stuart Grant

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Triumph Motorcycles has, like all British motor manufacturers, endured plenty of turmoil since its founding 120-odd years ago. But unlike so many Brit brands it survives today, thriving with a range of technically advanced machines and a healthy dose of retro-styled offerings that pay homage to a number of its iconic bikes of the past. Proudly standing in the brand’s keystone position is the Bonneville. Hang on… Bonneville... British? True, it’s the name of the expansive salt flats in Utah, but it’s also the spiritual home of American speed record-setting and the place where a Triumph-powered projectile set the fastest motorcycle world record.

This happened in September 1955, with Texan Johnny Allen clocking a two-way average speed of 193.3mph (311km/h) on his ‘Texas Cee-Gar’ streamliner – a 650cc twin-cylinder, methanol-fed special. While the American Motorcycle Association backed the record, the FIM refused as no official observers had been present. But it was enough to spark interest from the German maker NSU, who upped the record within a year. Allen returned in September 1956 and won back the pride for America and Triumph with an average of 214.17mph (344km/h). Again the FIM put a spanner in the works, but the publicity Triumph gained from the legal battle that ensued was substantial. So much so that when Triumph launched its 650cc T120 (model number continuing the fashion of proposed top speed in mph) at the 1959 Earls Court Bike Show, it was named the Bonneville and designer Edward Turner publicly referred to Triumph as “the world’s fastest motorcycles.”

With America being the largest market for Triumph leading up to 1959, the use of the name Bonneville was a shrewd move indeed. And it’s not the only bit of international flair that the best of British had – there’s some German in every Triumph, too. Triumph Engineering Co Ltd got underway when Siegfried Bettmann, who had emigrated from Nuremberg, founded the S. Bettmann & Co. Import Export Agency in London. His focus was on bicycles, which were imported and sold, but he also dabbled in German sewing machine distribution. In 1886, Bettmann changed the name to the Triumph Cycle Company and a year on registered it as New Triumph Co. Ltd, with funding from the Dunlop Pneumatic Tyre Company. Fellow German Moritz Schulte joined as a partner at this time and encouraged the shift from importer to manufacturing operation. Property was purchased in Coventry with cash from their families and the first Triumph-branded bicycles were produced in 1889. A second factory was opened in Nuremberg in 1896 and within two years, the Coventry site started testing waters with motorcycle production. The first real production Triumph motorcycle was released in 1902, essentially a Triumph bicycle with Belgian Minerva engine.

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From there on Triumph grew into a major motorcycling force, initially boosted by the supply of military machines during WWI; 30 000 or so bikes like the Model H Roadster ‘Trusty Triumph’ were supplied to the Allies. Triumph survived the Great Depression by selling its Nuremberg and Bicycle manufacturing operations. It was tough though, and Bettmann was forced out of the job of chairman and retired fully in 1933. In 1936, the motorcycle business was acquired by Ariel Motorcycle Company boss Jack Sangster and exports across the pond got underway. This market soon became the most important for Triumph. With the Ariel connection came designer Edward Turner, who in September 1937 designed the 500cc 5T Triumph Speed Twin, which formed the basis for all Triumph twins until the 1980s.

Following the obliteration of the factory during the WWII Coventry Blitz (7 September 1940 to May 1941), tooling and machinery was recovered and moved to a new plant in Meriden, Warwickshire, where Triumph production restarted in 1942. After the war, Turner’s Triumph Speed Twin design continued and in an effort to settle the Lend-Lease (an American programme to provide its allied nations with aid and military material) debts, nearly 70% (made up of Speed Twin and Tiger 100 models) of Triumph’s post-war production was shipped to the United States.

But America wanted more. More performance that is. Turner responded in ’49 by increasing the 500 Speed Twin’s bore and stroke to give 649cc. This hit the market as the 6T Thunderbird in 1950, and a Tiger T110 (indicating it could hit 110mph) hit the roads in ’53. The additional power had a downside though, and this was heat that was generated when being pushed hard. A solution came in ’56 when a new alloy cylinder head, known as the ‘Delta head’, replaced the iron units. Not only did the heat dissipate more efficiently but the bigger valves, better gas flow, higher compression and weight reduction improved the get-up-and-go noticeably.

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Is it ever enough? Not when it comes to bikes and performance, and the Triumph fans got a bit more oomph in the form of a twin-carburettor head option for the 650. It was this set-up that led to Turner’s final production Triumph design – the T120 Bonneville. At the core was the T10’s 649cc parallel-twin engine but a pair of Amal Monobloc carburettors were now standard, as was a high-performance inlet camshaft. The result was better than anyone could have expected, and the Bonneville rocketed to the sharp end of the fastest production bike list, scoring many victories on both road and track – although the T120 tag might have been a bit ambitious as it seems 115mph was the more realistic top speed.

It was a touch scary up at these figures though, with the single downtube frame not up to scratch in the rigidity department and speed wobbles the order of the day. Fans and potential clients were also not exactly blown away by the looks; the streamlined nacelle headlight and fully sided mudguards were a bit dated. These were remedied in 1960 while additional bracing at the steering head and swinging arm fixed the wobbles in ’63 (this was improved upon a few years later with better front fork set-up and modification of the steering angle). In 1963, the 650 twin engine also had a major refresh with the separate crankcase, primary case and transmission being replaced with one single housing.

Motorsport the world over (from track and road racing in Europe to off-roading in the USA) saw the Bonneville pushed to its limits and the continual experimentation saw numerous refinements trickling down to the road machines. As the 1960s came to a close and the ’70s took off, the T120 Bonneville reached its peak; many considered it an almost perfect combination of horsepower, good handling and lack of vibration – impressive considering it was essentially a 1930s design.

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But was it really that good? Not if you’d ridden one of the up-and-coming Japanese models. Honda’s CB450 was as fast (although reports say the T120 still handled better) and the 750 Four made the Triumph look a little silly – as did the Kawasaki 500 triple. These machines were cheaper and way more reliable, too.

Triumph needed to react – and react quickly – with technology like a five-speed gearbox, electric starter and disc brakes. But all the firm’s owners, now BSA, really managed to accomplish was an inter-company rivalry between its own brands and swallowing up much-needed cash. A healthy portion of money went into the development of a frame that both brands used for their respective 650 twins in 1971. Designed by aerospace engineers and not bikers, it was the answer to the question no one was asking: how do we get rid of the oil tank? So what we got was the oil-in-frame, which as the name suggests saw the oil tank removed and the liquid now housed in the frame. Odd when you consider that the handling was the one department where the T120 was ahead of the Japanese bikes.

Finalising the design and setting up the tooling for it meant that the production line was stopped for weeks and when the first of these new frames arrived, it was discovered that the engines didn’t fit. After a rethink and adaption, the oil-in-frame continued to be a problem for the Bonneville – the frame spine that should have been filled to the brim could only be filled halfway thanks to foaming issues and this led to plenty of broken engines, with inadequate oil supply being the reason.


T120 production soldiered on but a 750cc T140 version arrived to steal some thunder in 1972 – this was Triumph’s hopeful answer to the onslaught of the larger-capacity competition. Production of the T120 and T140 ran alongside each other until 1973 when striking workers staged a go-slow sit-in that lasted until 1975. Fewer than 1 000 650cc versions left the factory in this period and when the strike ended, only T140 production resumed. In this guise, the Bonneville story ambled on until 1983 when Triumph Engineering, now owned by its workers, went into liquidation and the doors shut.

How, then, can I walk into a Triumph dealership and buy a new Bonneville? We can thank British billionaire John Bloor for stepping in and buying the business. Registered as Triumph Motorcycles Ltd, his plan was to re-engineer the old bikes, but he soon abandoned that idea in favour of a whole new bike. While the planning of this took place, he licensed the rights and tooling to Les Harris, who released a number of limited-edition classic 750 Bonnevilles between 1985 and ’88.

By this time, Bloor had put together a formidable team, hired several of the group’s former designers to work on some all-new models and funded the building of a new factory at a 40 000m2 site in Hinckley, Leicestershire. A major portion of the focus and strategy was on a new line of three- and four-cylinder bikes built around 250cc and 300cc component sets – the maths reveals a bunch of 750cc and 900cc triples as well as 1000cc and 1200cc fours. These rocked the roads from 1991 and it took another 10 years until the much-loved Bonneville returned. It was more than just a name though, sporting an aesthetic not too far off the original and seeing a twin as the power source – this time a modern 800cc DOHC four-valve-per-cylinder, good for 65 horses.

Today, a new Bonneville T120 will set you back about R165 000 and comes with a 1200cc water-cooled parallel twin producing 79bhp. Transmission is now a slick six-speed gearbox, braking is done by discs with ABS and fuelling comes courtesy of a multipoint sequential electronic injection that not only means easier cold starts but also seriously improved fuel economy. There’s a 900cc Bonneville T100 too, as well as some other iconic-named modern classics like the Speed Twin, Thruxton, Bobber and Scrambler that sell alongside various sporting, touring and adventure offerings from the British hero. Like the 1960s Bonneville heyday, the vast majority are made for the export market – something like 85% leave the UK for other regions, and thankfully South Africa is one of those.

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