Norton Dominator
Encyclopedia
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.
This design set the pattern for Norton twins for the next 30 years.
The Model 7 continued in production through to 1955 and was often used with a side car as they could not be fitted to the Featherbed frame
Dominators.
It was this new Featherbed frame that led to the Model 88 Dominator, also called the Dominator De Luxe, which used the same 497 cc engine and was developed in 1951. Originally developed for export it was sold on the home market from 1953. The 88 suffered from oil leaks from the primary chain case but it was the outdated and inefficient Norton works that resulted in quality control problems for the 200 Model 88's produced each week.
The 596 cc Model 77 Dominator was introduced in late 1956. Essentially a swinging arm, single downtube ES2 chassis with a 600 cc Dominator 99 engine, it was in production at the same time as the Dominator 99 as a sidecar motorcycle but was dropped from production after 1957, when sidecar Featherbeds were introduced.
. Doug Hele
wanted to see the Dominator developed and produced a 55 bhp "Domiracer" that revved to 8,000 rpm. The Domiracer weighed 35 lb (15.9 kg) less than the Manx. Dennis Greenfield and Fred Swift won the 500 cc class in the Thruxton 500
event in 1960 and Tom Phillis took the bike to third place and lapped at over 100 mph (45 m/s), a first for a pushrod motor and a first for any twin in the 1961 Isle of Man TT
. Norton abandoned the Domiracer project a year later when the Bracebridge Street race shop closed and the Domiracer and factory spares were sold to Paul Dunstall, who continued with development and began producing Norton performance parts, eventually selling complete Norton Dunstall
bikes, to customers including Steve McQueen
.
Motorcycle
A motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...
developed by Norton to compete against the Triumph Speed Twin
Triumph Speed Twin
The Speed Twin 5T is a motorcycle that was made by Triumph at their Coventry factory. Edward Turner, Triumph’s Chief Designer and Managing Director, launched the Triumph Speed Twin at the 1937 National Motorcycle Show. It was a 500 cc OHV vertical twin in a lightweight frame and the first...
. The original Dominator was designed in 1947 and 1948 by Bert Hopwood
Bert Hopwood
Herbert "Bert" Hopwood was a British motorcycle designer. He helped with some of the most influential designs for the British motorcycle industry and worked for Ariel, Norton, BSA and Triumph.-Motorcycle design career:...
, who had been on the Speed Twin design team at Triumph.
This design set the pattern for Norton twins for the next 30 years.
Model 7
The Dominator Model 7 had a 497 cc iron head iron cylinder parallel twin engine with a plunger frame and a Lucas K2F magneto. Norton stuck with a 360-degree crankshaft layout with a single camshaft at the front of the engine driven by gears and chain. Having the rockers integral with the head meant there were less gasket faces to leak, and less valve noise. The 66 millimetre bore and stroke engine was a long stroke design, with mild tuning, resulting in more torque low down. In 1953 the Model 7 was upgraded with a single downtube swinging arm frame, 19-inch front wheel and 'pear shaped' silencers, still known as a Model 7.The Model 7 continued in production through to 1955 and was often used with a side car as they could not be fitted to the Featherbed frame
Featherbed frame
The featherbed frame was a motorcycle frame developed by the British Norton motorcycle company to improve the performance of their racing motorcycles around the twisting and demanding Isle of Man TT course in 1950. It was considered revolutionary at the time, and the best handling frame that a...
Dominators.
Model 88
The Featherbed frame, designed for Norton by the McCandless brothers, were made by the Reynolds company as the outdated Norton works did not have the necessary modern welding capacity for its manufacture.It was this new Featherbed frame that led to the Model 88 Dominator, also called the Dominator De Luxe, which used the same 497 cc engine and was developed in 1951. Originally developed for export it was sold on the home market from 1953. The 88 suffered from oil leaks from the primary chain case but it was the outdated and inefficient Norton works that resulted in quality control problems for the 200 Model 88's produced each week.
Model 99
The 596cc featherbed framed Model 99 Dominator was introduced in 1956, as a larger capacity version alongside the 500 cc Model 88 version. Due to the increased engine capacity, the 99 had a power output of 31 bhp, partly due also to a higher compression ratio possible with the alloy head introduced a year earlier. Full width alloy hubs with improved brakes had also been introduced a year earlier, preparatory for the capacity increase from 500 cc to 600 ccModel 77
The first Model 77 was a rigid framed telescopic forked Dominator version of 500 cc produced from 1950, and supplied to the Australian market only. Only a few hundred were made, from 1950 to 1952. This used the all iron Dominator 500 cc twin engine, but with an oil pressure gauge in the tank.The 596 cc Model 77 Dominator was introduced in late 1956. Essentially a swinging arm, single downtube ES2 chassis with a 600 cc Dominator 99 engine, it was in production at the same time as the Dominator 99 as a sidecar motorcycle but was dropped from production after 1957, when sidecar Featherbeds were introduced.
Slimline Featherbed frames for 1960
From 1960, the featherbed frame for all Dominators was altered so that the frame tubes in front of the seat were narrower, for improved rider comfort. The seats and tanks and indeed the whole styling of the Dominator was redesigned to suit. A large metal tank badge completed the look, along with some 2 toned paint schemes. And some optional enclosed body styling on the "Deluxe" Models of the 88 and 99, along the lines of the 'bathtub' Triumph models.1960 Manxman 650 and 1961 Dominator 650SS
A new 650 cc model was added to the lineup for 1960. The featherbed frame was altered so that the top rails were closer together at the front of the seat area to create what became known as the 'slimline featherbed'. A 650 cc engine was installed to create the Norton Manxman. First built from 7 November 1960 to September 1961, these machines were a Limited Edition for the USA only, in custom-cruiser style - with high handlebars, all Polychromatic blue paint and Bright red seat With white piping round the edge . In September 1961 the 650SS was introduced. It had USA cafe bar style and twin carburettors. The SS stood for Super Sports and the 600 cc models were discontinued to concentrate on production of the 650SS, which quickly earned a reputation as the "best of the Dommies".Racing
The Norton factory racing team briefly used race-tuned twin cylinder Dominators from circa 1960, but they were still outclassed by the Norton ManxNorton Manx
The Norton Manx or Manx Norton is a British racing motorcycle that was made from 1947 to 1962 by Norton Motors Ltd. A Norton had contested every Isle of Man TT race from the inaugural 1907 event through into the 1970s, a feat unrivalled by any other manufacturer, and the development and honing of...
. Doug Hele
Doug Hele
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 the 2 November 2001.-Career:...
wanted to see the Dominator developed and produced a 55 bhp "Domiracer" that revved to 8,000 rpm. The Domiracer weighed 35 lb (15.9 kg) less than the Manx. Dennis Greenfield and Fred Swift won the 500 cc class in the Thruxton 500
Thruxton 500
The Thruxton 500 is a 500 mile motorcycle endurance race held at Thruxton Circuit, near Andover in Hampshire, United Kingdom, which is the fastest racetrack in the country...
event in 1960 and Tom Phillis took the bike to third place and lapped at over 100 mph (45 m/s), a first for a pushrod motor and a first for any twin in the 1961 Isle of Man TT
Isle of Man TT
The International Isle of Man TT Race is a motorcycle racing event held on the Isle of Man and was for many years the most prestigious motorcycle race in the world...
. Norton abandoned the Domiracer project a year later when the Bracebridge Street race shop closed and the Domiracer and factory spares were sold to Paul Dunstall, who continued with development and began producing Norton performance parts, eventually selling complete Norton Dunstall
Norton Dunstall
The Dunstall was a Norton motorcycle made by Paul Dunstall, a specialist tuner of 1960s and early 1970s twins using parts from Norton's Domiracer project when the Birmingham factory was closed in 1963...
bikes, to customers including Steve McQueen
Steve McQueen
Terrence Steven "Steve" McQueen was an American movie actor. He was nicknamed "The King of Cool." His "anti-hero" persona, which he developed at the height of the Vietnam counterculture, made him one of the top box-office draws of the 1960s and 1970s. McQueen received an Academy Award nomination...
.