Triton motorcycle

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Pre-unit construction 650 cc Triumph twin-cylinder engine in a Norton 'wideline' Featherbed frame Triton.jpg
Pre-unit construction 650 cc Triumph twin-cylinder engine in a Norton 'wideline' Featherbed frame

Triton motorcycles were hybrid motor cycles built from the 1950s to the 1970s[ citation needed ] that involved fitting Triumph engines into Norton frames. Because no factory offered Triton motorcycles, they were typically privately built. However, some UK dealers offered complete bikes. [1] The aim was to combine the best elements of each marque and thus gain a bike superior to either. The name 'Triton' is a contraction of Triumph and Norton; 'Triton' was the name of an ancient Greek god.

Contents

During the period in which Triton motorcycles were constructed, the Norton featherbed frame was regarded as the best handling frame. [2] [3] Triton bikes aimed to combine the "best engine" with the "best frame" by replacing the standard Norton engine with a Triumph parallel-twin engine. Although "best" is subjective, a popular engine choice was the Triumph Bonneville unit with twin carburettors and twin camshafts. This pushrod engine gave good performance and reliability and could be more easily tuned for greater power using high-profile camshafts, high compression pistons and twin carburettors. In due course, a Weslake 8-valve head became available for the Triumph motor.

The Triumph engine was seen as an upgrade because the Norton 650 and 750 vertical twin engines were known to have reliability problems.[ citation needed ] At about 7000 rpm the piston exceeds the engineering limit for piston speed, so over-revving soon destroys the engines. The BSA 650 had a bronze bush main bearing on the right hand side, doubling as the crank oil feed, with a lack of effective crankshaft end play control, that all had difficulty staying together when ridden hard, even though the rest of the design was possibly more robust than the Triumph. The Triumph vertical twin used a ball on the timing side, and a roller on the other, with the oil feeding through a separate bronze bush in the outer right hand engine side cover.

650 cc Triumph twin-cylinder engine in a Norton "slimline" featherbed frame Triton Peter Ritzen.jpg
650 cc Triumph twin-cylinder engine in a Norton "slimline" featherbed frame

Whereas the Norton 650SS 646.44 cc had a bore and stroke of 68 x 89 mm giving 49 bhp (37 kW) @ 6,800 rpm, the Triumph T120 Bonneville 649.31 cc had a bore and stroke of 71 x 82 mm giving 46 bhp (34 kW) @ 6,500 rpm. However the mean piston speed of the Norton was 3,971 ft/min (almost at the, then accepted, limit of 4,000 ft/min). The Triumph, with its shorter stroke, had a mean piston speed of only 3,497 ft/min, had much less vibration and was much stronger and reliable. Road tests showed that the Norton had a higher top speed due to its 3 bhp (2.2 kW) advantage. In spite of this, the Triumph was the much preferred engine. The Norton featherbed was the preferred frame, hence the Triton.

Tritons with a pre-unit Triumph motor sometimes retained the post-1960 Norton AMC gearbox, which was thought superior to the equivalent Triumph gearbox. A Quaife five speed gearbox was sometimes used. More modern Tritons use a Triumph unit construction twin in a Featherbed frame.

Several motorcycle dealers made equipment for Triton conversions, some would do the complete job for customers while others sold complete Tritons. The most important part required are the engine mounting plates and several different designs exist that can affect the engine placement and therefore the handling. The lower the engine is mounted the better the handling achieved from the Norton frame.

Other hybrids

A "Norbsa" with a BSA chassis and Norton Commando 850cc engine BSA Commando Worcester Street right.jpg
A "Norbsa" with a BSA chassis and Norton Commando 850cc engine

The Triton was probably the most common hybrid British motorcycle. Others include the Tribsa, with a Triumph engine in a BSA frame; the Norvin, with a Vincent V-twin engine in a Norton featherbed frame; [4] and a Trifield with a Triumph engine in a Royal Enfield frame. A "Norbsa" may be either a BSA engine in the Norton featherbed frame, or a Norton engine in a BSA frame.

Related Research Articles

<span class="mw-page-title-main">Norton Motorcycle Company</span> British motorcycle manufacturer

The Norton Motorcycle Company is a brand of motorcycles headquartered in Solihull, West Midlands,, England. For some years around 1990, the rights to use the name on motorcycles was owned by North American financiers.

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 1980s and is now one of the world's major motorcycle manufacturers.

<span class="mw-page-title-main">Matchless</span> British motorcycle and automobile manufacturer

Matchless is one of the oldest marques of British motorcycles, manufactured in Plumstead, London, between 1899 and 1966. A wide range of models were produced under the Matchless name, ranging from small two-strokes to 750 cc four-stroke twins. Matchless had a long history of racing success; a Matchless ridden by Charlie Collier won the first single-cylinder race in the first Isle of Man TT in 1907.

<span class="mw-page-title-main">BSA Rocket 3/Triumph Trident</span> 1960s/1970s British motorcycle made by Triumph Engineering, Meriden

The Triumph Trident and BSA Rocket 3 was a technically advanced, high-performance roadster motorcycle made by Triumph Engineering and BSA from 1968 to 1975, and sold under both the Triumph and BSA marques. Alongside the Honda CB750, and later the two-stroke Kawasaki triples, it brought a new level of sophistication to street motorcycles, marking the beginning of the superbike era. The Honda CB750 overshadowed the Trident to be remembered as the 'first superbike', in spite of the Triumph Trident actually debuting before the Honda by a few weeks.

<span class="mw-page-title-main">Triumph Bonneville</span> Type of motorcycle

The Triumph Bonneville is a standard motorcycle featuring a parallel-twin four-stroke engine and manufactured in three generations over three separate production runs.

Norton-Villiers was a British motorcycle manufacturer formed in the 1960s following the collapse of AMC. With the general decline of the British motorcycle industry, under a British Government initiative it was later combined with the remnants of BSA Triumph to form Norton-Villiers-Triumph.

<span class="mw-page-title-main">Doug Hele</span> British motorcycle engineer

Douglas Lionel Hele was a pioneering British motorcycle engineer with Triumph and other firms: BSA, Douglas and Norton. He was born in Birmingham in 1919 and died in Hagley, Worcestershire on 2 November 2001.

<span class="mw-page-title-main">Norton Dominator</span> Type of motorcycle

The Dominator is a twin cylinder motorcycle developed by Norton to compete against the Triumph Speed Twin. The original Dominator was designed in 1947 and 1948 by Bert Hopwood, who had been on the Speed Twin design team at Triumph. Available for sale from mid 1949, this design set the pattern for Norton twins for the next 30 years.

<span class="mw-page-title-main">Norton Atlas</span> Motorcycle powered by straight-twin engines

The Norton Atlas was a Norton motorcycle made between 1962 and 1968, until it was replaced by the Norton Commando.

<span class="mw-page-title-main">Featherbed frame</span> Motorcycle frame

The featherbed frame was a motorcycle frame invented by the McCandless brothers and offered to the British Norton motorcycle company to improve the performance of their racing motorcycles in 1950. It was considered revolutionary at the time, and the best handling frame that a racer could have. Later adopted for Norton production motorcycles, it was also widely used by builders of custom hybrids such as the Triton, becoming legendary and remaining influential to this day.

<span class="mw-page-title-main">BSA Road Rocket</span> Type of motorcycle

The BSA Road Rocket was a 1950s 646 cc (39.4 cu in) air-cooled parallel twin motorcycle designed by Bert Hopwood and produced by Birmingham Small Arms Company (BSA) at Small Heath, Birmingham. Developed from the A10 Golden Flash it was the first sports bike in the BSA A10 series. The A10 had a reputation for reliability but was struggling to compete against the Triumph engines and the Norton Featherbed frames. Advertised by BSA in 1956 as 'undoubtedly the world's greatest motor cycle' the Road Rocket was discontinued in 1958 when it was replaced by the BSA Super Rocket.

<span class="mw-page-title-main">BSA A7</span> Motorcycle

The BSA A7 was a 500cc motorcycle model range made by Birmingham Small Arms Company (BSA) at its factory in Armoury Road, Small Heath, Birmingham. The range was launched in 1946 using a 495 cc (30.2 cu in) long stroke engine. An improved 497 cc (30.3 cu in) version based on the BSA A10 engine was launched in 1950. The various A7 models continued in production with minor modifications until 1961/2 when they were superseded by the unit-construction A50 model.

<span class="mw-page-title-main">Triumph Bonneville 790</span> British motorcycle

The Triumph Bonneville 790 cc is a British motorcycle that was designed and built in Hinckley, Leicestershire by Triumph Motorcycles Ltd between 2001 and 2007, when the engine size was increased to 865 cc.

<span class="mw-page-title-main">Norton Isolastic frame</span>

The isolastic frame, designated by Norton as GlideRide, used a system of engine-to-frame mountings incorporating rubber bushes to isolate the vibration of the vertical twin engine from the frame and rider. The isolastic frame was developed for use with the Commando inclined engine, whilst the Featherbed frame continued in production for the Mercury with a softer-specification 650 cc vertical-engine until 1970.

<span class="mw-page-title-main">BSA motorcycles</span> Former British motorcycle marque

BSA motorcycles were made by the Birmingham Small Arms Company Limited (BSA), which was a major British industrial combine, a group of businesses manufacturing military and sporting firearms; bicycles; motorcycles; cars; buses and bodies; steel; iron castings; hand, power, and machine tools; coal cleaning and handling plants; sintered metals; and hard chrome process.

<span class="mw-page-title-main">BSA A10 series</span> Motorcycle

The BSA A10 series was a range of 646 cc (39.4 cu in) air-cooled parallel twin motorcycles designed by Bert Hopwood and produced by Birmingham Small Arms Company at Small Heath, Birmingham from 1950 to 1963. The series was succeeded by the A65 unit construction models.

<span class="mw-page-title-main">Norton Model 7 Dominator</span> Type of motorcycle

The Norton Model 7 Dominator was a 500 cc vertical twin motorcycle manufactured by the Norton Motorcycle Company from 1949 to 1955. It was the first of Norton's Dominator range of motorcycles. The engine was designed by Bert Hopwood and was a departure from Norton's previous practice of producing single-cylinder machines. The Model 7 was used in Japan as a police motorcycle.

<span class="mw-page-title-main">Norton Model 88 Dominator</span> Type of motorcycle

The Norton Model 88 Dominator, also originally known as the Dominator De Luxe was a 500 cc vertical twin motorcycle manufactured by the British Norton Motorcycle Company from 1952 to 1966. It was the first of Norton's motorcycles to use the featherbed frame, which established Norton's reputation of producing fine handling machines. The 88 used the Bert Hopwood designed engine that was first fitted to the Model 7 and was initially for export only. It became available on the home market in 1953. Norton were a small manufacturer at the time and without the economies of scale the model was expensive compared to other manufacturer's equivalent machines. The 88 retailed for 20% more than the contemporary Triumph Speed Twin and was dearer than the 650 cc Triumph Thunderbird.

<span class="mw-page-title-main">Norton Model 99 Dominator</span> Type of motorcycle

The Norton Model 99 Dominator was a 600 cc vertical twin motorcycle manufactured by the British Norton Motorcycle Company at their Bracebridge St, Birmingham factory from 1956 to 1962. The 99 was based on the 500 cc Model 88 Dominator with an enlarged engine. The model was superseded by the 650SS.

The Norton Manxman was a 650 cc vertical twin motorcycle manufactured by the British Norton Motorcycle Company at their Bracebridge St, Birmingham factory for export. The engine was an enlargement of the 600 cc engine used in the Model 99 Dominator. The Manxman was first shown at the November 1960 Earls Court Motorcycle Show and listed by the American importer, Berliner, in their catalogue from 1961 to October 1962 Berliner had asked for the model to be named Manxman although the twin had never been raced at the Isle of Man.

References

  1. Brown, Roland (15 September 2022). "The original Dresda Triton is a loveable mongrel with race-winning pedigree". Hagerty International Limited. Retrieved 22 May 2024.
  2. Foale, Tony (2006). Motorcycle Handling and Chassis Design: The Art and Science. Tony Foale. ISBN   9788493328634.
  3. Walker, Alastair (2009). The Cafe Racer Phenomenon. Veloce Publishing Ltd. ISBN   9781845842642.
  4. Norvin technical section thevincent.com (retrieved 18 November 2007)