The Triumph Bonneville T120 is a

motorcycle A motorcycle (motorbike, bike; uni (if one-wheeled); trike (if three-wheeled); quad (if four-wheeled)) is a lightweight private 1-to-2 passenger personal motor vehicle Steering, steered by a Motorcycle handlebar, handlebar from a saddle-style ...

originally made by

Triumph Engineering Triumph Engineering Co Ltd was a British motorcycle manufacturing company, based originally in Coventry and then in Meriden. A new company, Triumph Motorcycles Ltd, based in Hinckley, gained the name rights after the end of the company in the ...

from 1959 to 1975. It was the first model of the Bonneville series, which was continued by

Triumph Motorcycles Ltd Triumph Motorcycles Ltd is the largest UK-owned motorcycle manufacturer, established in 1983 by John Bloor after the original company Triumph Engineering went into receivership. The new company, initially called Bonneville Coventry Ltd, contin ...

. The T120 was discontinued in favour of the larger 750 cc

T140 T14 may refer to: Aerospace * T14 (satellite), a DirecTV communications satellite * Slingsby T.14 Gull II, a British glider * Soyuz T-14, the 9th expedition to Salyut 7 * Taylor Airport (Quinlan, Texas) Education * Top 14 Law Schools, the ...

in the early 1970s.

Development

The Bonneville T120 was Edward Turner's last production design at Triumph (in retirement Turner designed the Triumph Bandit/BSA Fury which did not pass the prototype stage before BSA went under). The new motorcycle was conceived and developed so quickly that it was not included in the 1959 Triumph catalogue. With a parallel-twin (two-cylinder) engine the T120 was based on the

Triumph Tiger T110 The Triumph Tiger 110 is a British sports motorcycle that Triumph first made at their Coventry factory between 1953 and 1961. The T110 was developed from the Triumph Thunderbird and first appeared in 1954. Although it was supposed to be the ...

and was fitted with the Tiger's optional twin 1 3/16 in

Amal Monobloc AMAL was a British engineering company servicing the motorcycle and other light-engineering motor industries between 1927 and 1993 Launched in 1959 by Triumph as "The Best Motorcycle in the World", the Bonneville T120 was aimed mainly at the lucrative US market where enthusiasts were demanding extra performance. Initially produced with a pre-unit construction engine which enabled the bike to achieve without further modification, the power tended to induce high speed wobbles from the single downtube frame, so in 1963 a stiffer and more compact

unit construction : ''For the vehicle design where the vehicle's skin is used as a load-bearing element, see Monocoque.'' Unit construction is the design of larger motorcycles where the engine and gearbox components share a single casing. This sometimes includes ...

model was introduced, with additional bracing at the steering head and swinging arm. The steering angle was altered and improved forks were fitted a couple of years later, which, together with the increased stiffness enabled overall performance to match that of the Bonneville's rivals. In 1967 Triumph posted its most successful year in the United States with an estimated 28,000 T120s sold. In 1968 the T120 gained a new and more reliable ignition system. From 1971, T120 models used a new frame which contained the engine oil instead of using a separate tank (this became known as the ''oil in frame''/'OIF' version). A five-speed gearbox finally was fully available by 1972, but competition from larger-capacity motorcycles led to the T120 being superseded by the 750 cc Bonneville T140. Production of the 650 continued until 1973, when the workers at Triumph's Meriden headquarters staged a sit-in until 1975. In 1974 fewer than 1000 of the 650cc assembled machines were released by the workers, with another 38 in 1975. Production of the T120 was not resumed following the sit-in, the Meriden Motorcycle Co-Operative created after the dispute concentrating upon the 750cc twins instead.

T120 export models

*T120R :Export model intended for the US market with in varying years, varying differences. *T120V :5-speed model available 1972. *T120C :Competition model with high-level exhaust pipes. *T120TT :1964 model of the T120C for the US East Coast. In 1968

Evel Knievel Robert Craig Knievel (October 17, 1938November 30, 2007), known professionally as Evel Knievel (), was an American stunt performer and entertainer. Throughout his career, he attempted List of Evel Knievel career jumps, more than 75 ramp-to-ra ...

jumped the Caesar's Palace Casino fountains on a Bonneville T120TT, and was seriously injured breaking many bones after losing control on landing. Triumph T120 650cc 1967 - Flickr - mick - Lumix

Triumph T120 650cc 1967 - Flickr - mick - Lumix

*T120RT :A special 750 cc model which had Routt 750cc cylinder kits installed in America by Triumph to permit them to be used in

American Motorcycle Association The American Motorcyclist Association (AMA) is an American nonprofit organization of more than 200,000 motorcyclists that organizes numerous motorcycling activities and campaigns for motorcyclists' legal rights. Its mission statement is "to pro ...

production-based racing events. The kits were installed on new T120R models while still crated. To qualify, motorcycles had to be made and sold to the public in the same form as they would be raced. Triumph had to produce and sell at least 200 of them before they qualified, and although the exact number sold is not recorded they did meet the requirement. The T was stamped separately on the engine cases in America after the stock T120R when the modifications were made, the frames were not stamped. *T120RV :The 5-speed is generally considered to have been available—and was advertised as such—starting in 1972 with the T120V. However, a small pre-production run of 5-speeds were made in June 1971 only, and sold as '71 models. They were externally identical to their '71 T120R 4-speed counterparts, and did not carry any "V" decals such as the 1972 5-speeds displayed on their side panels. They were factory (not dealer) modified T120R models, so their engines/frames/and titles are designated T120RV, with the V being stamped separately when the transmissions were installed. :These early factory Triumph 5-speeds are not to be confused with the Quaife 5-speeds that were listed as stocked for sale by Triumph dealers in 1970 to qualify for AMA purposes (the parts "had to be available from Triumph"). The first and final T120RV ratios in 1971 were the same as the 4-speed model, making it a matter of closer ratios, unlike later 5-speeds. These 5-Speeds were not advertised, were not available as an option, and could not be ordered—as the few manufactured were simply distributed individually to selected Triumph dealers and sold by word of mouth.

Racing success

The first race the Triumph Bonneville participated in was the 1959 Thruxton 500. Entered by Triumph dealers including Alec Bennet and Kings Motors (run by owner Stan Hailwood, Mike Hailwood's father) with bikes supplied from the factory, in this first race they finished 2nd, with riders Tony Godfrey/John Holder (behind a BMW) and 4th, riders Arthur Burton/Charles Erskine; the beginning of a successful era of Triumph motorcycle racing. In 1962 Tony Godfrey and John Holder rode T120 Bonnevilles to victory in the Thruxton 500 mile endurance race, and an article in ''

The Motor Cycle ''The Motor Cycle'' was one of the first British magazines about motorcycles. Launched by Iliffe and Sons Ltd in 1903, its blue cover led to it being called "The Blue 'un" to help distinguish it from its rival publication ''Motor Cycling (mag ...

'' entitled "Thruxton Triumph by Bonneville" led to the development of the Triumph T120R 'Thruxton', which was hand-built by a team of Triumph technicians using specially picked components and precision-machined cylinder heads and crankcases. Peak power was increased and each 'Thruxton' engine was bench tested to deliver around at 6,800 rpm with a safe rev ceiling of 7,200 rpm. Only 52 of the Thruxton T120Rs were built in 1964/5 to meet homologation requirements for production racing, and surviving examples are rare. About 100 more machines were subsequently manufactured and supplied to selected dealers and riders. Further examples were also built by dealers, with the factory's approval, from factory supplied parts. The T120 won the Production

Isle of Man TT The Isle of Man TT or Tourist Trophy races are an annual motorcycle racing event run on the Isle of Man in May and June of most years since its inaugural race in 1907 Isle of Man TT, 1907. The event begins on the UK Spring Bank Holiday at the e ...

1967 Events January * January 1 – Canada begins a year-long celebration of the 100th anniversary of Canadian Confederation, Confederation, featuring the Expo 67 World's Fair. * January 6 – Vietnam War: United States Marine Corps and Army of ...

and

1969 1969 ( MCMLXIX) was a common year starting on Wednesday of the Gregorian calendar, the 1969th year of the Common Era (CE) and ''Anno Domini'' (AD) designations, the 969th year of the 2nd millennium, the 69th year of the 20th century, and the ...

in the 501–750 cc classification. The re-introduction of the Production TT was in 1967 when

John Hartle John Hartle (22 December 1933 – 31 August 1968) was an English professional road racer who competed in national, international and Grand Prix motorcycle events. Motorcycling career Born in Chapel-en-le-Frith, Derbyshire, Hartle began ra ...

took first place. Two years later in

, Triumph set a new landmark in TT history when

Malcolm Uphill Malcolm Ernest Uphill (15 April 1935 – 15 August 1999) was a Welsh professional motorcycle racer. He competed in British national-level short-circuit and in Grand Prix motorcycle racing. Uphill was the first competitor in the Isle of Man ...

averaged around the Mountain Course on a Bonneville. Uphill's achievement was the first time that a production motorcycle had ever passed the three-figure mark from a standing start. Following Uphill's record, the Dunlop K81 tyres he was using were renamed

TT100 The Thebes, Egypt, Theban Tomb TT100 is located in Sheikh Abd el-Qurna, part of the Theban Necropolis, on the west bank of the Nile, opposite to Luxor. It is the mortuary chapel of the ancient Egyptian Vizier (Ancient Egypt), vizier Rekhmire. T ...

s. In 1969, Bonneville T120 bikes achieved the first three places in the Thruxton 500.

Percy Tait Percy Tait (9 October 1929 – 17 November 2019) was an English professional motorcycle road racer and senior road tester for Triumph motorcycles, where he was estimated to have covered over a million miles of road testing. He later became a ...

and co-rider Malcolm Uphill finished first, ahead of two other Triumph T120Rs. In 2012, Marc LaNoue set a Vintage class record at the

Pikes Peak International Hill Climb The Pikes Peak International Hill Climb (PPIHC), also known as The Race to the Clouds, is an annual automobile Hillclimbing, hillclimb to the summit of Pikes Peak in the U.S. state of Colorado. The track measures and has over 156 tur ...

.2012 Pikes Peak International Hill Climb results
topspeed.com Retrieved 25 December 2019

The Bonneville name

The Bonneville name came from the achievements of

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

racer Johnny Allen on the

Bonneville Salt Flats The Bonneville Salt Flats are a densely packed salt pan in Tooele County in northwestern Utah, United States. A remnant of the Pleistocene Lake Bonneville, it is the largest of many salt flats west of the Great Salt Lake. It is public land ma ...

Utah Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...

. In September 1955, Allen had achieved a two-way average speed of 193.3 mph (311 km/h) on his special motorcycle the "Devil's Arrow", a 650 cc twin-cylinder Triumph engine fuelled by

methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often ab ...

in a unique 'streamliner' fairing. Allen's speed was ratified as a record by the

but not by the world authority, the

FIM FIM may refer to: Organizations and companies * Fédération Internationale de Motocyclisme, the International Motorcycling Federation * Flint Institute of Music, in Michigan, United States * Fox Interactive Media, now News Corp. Digital Media * ...

, as no official observers were present. German motorcycle firm NSU took the record the following year, so Allen and his team returned to Bonneville in September 1956 and won it back with an average speed of 214.17 mph (344 km/h). The FIM also refused to accept this as a world record but Triumph gained much needed publicity from the legal dispute that followed. After the Bonneville T120 had been named in recognition of Allen's records, other Triumph-engined motorcycles went faster still on the Salt Flats. In 1962 Bill Johnson set a two-way average of 230.269 mph (370.5 km/h) over a measured mile, riding a 667 cc 'streamliner' whose design was based on the American X-15 rocket plane. In 1966

Detroit Detroit ( , ) is the List of municipalities in Michigan, most populous city in the U.S. state of Michigan. It is situated on the bank of the Detroit River across from Windsor, Ontario. It had a population of 639,111 at the 2020 United State ...

Triumph dealer Bob Leppan raised the record to 245.66 mph (395.3 km/h) with his

Gyronaut X-1 Gyronaut X-1 was a streamliner motorcycle that set the motorcycle land-speed record of in 1966, ridden by Detroit Triumph dealer Bob Leppan. It was powered by two 650 cc Triumph TR6 Trophy motorcycle engines. The streamlined body was design ...

, powered by two 650 cc Triumph engines. For the next few years, Triumph fitted Bonneville roadsters with "World's Fastest Motorcycle" stickers.

References

External links