Norton Commando
Encyclopedia
The Norton Commando is a British motorcycle
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...

 with an ohv pre-unit parallel twin engine, launched by the Norton Motorcycle company in 1967. Initially a nominal 750 cc displacement
Engine displacement
Engine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre . It is commonly specified in cubic centimeters , litres , or cubic inches...

, actually 745 cc, in 1973 it became an 850 cc, actually 828 cc.

During its ten years in production, the Commando was popular all over the world. In the United Kingdom it won the MCN "Machine of the Year" award for five successive years from 1968-1972. Given that its engine was an old pre-unit design, even Norton's chairman, Dennis Poore
Dennis Poore
Roger Dennistoun "Dennis" Poore was a British entrepreneur, financier and sometime racing driver,. Poore used his personal weath to bankroll the founding, in 1950, of the motor racing journal Autosport. He himself was a keen motor sport participant, and competed in two Formula One World...

, expressed surprise at the Commando's remarkable success.

Background

The origins of the Norton Commando can be traced back to the late 1940s when the 497 cc Norton Model 7
Norton Dominator
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....

 Twin, designed 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:...

 and initially an export only model. The twin cylinder design evolved into the 650 cc Norton Dominator
Norton Dominator
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....

 and 750 cc Norton Atlas
Norton Atlas
The Norton Atlas was a Norton motorcycle made by between 1962 and 1968, until it was replaced by the Norton Commando.-Development:The Mark 1 Atlas was launched as the 750SS in the early 1960s. Designer Bert Hopwood’s 497cc Dominator engine was bored and stroked out to 745cc, via 600cc and then...

 before being launched as the 750 cc Commando in 1967. As well as having a radical new frame, the Commando's parallel twin engine (which was mounted vertically in earlier models) was tilted forward. This was relatively easy as the engine was "pre-unit" (i.e. the gearbox was not integral with the crankcase), and the change gave three benefits: (i) the centre of gravity was moved further forward; (ii) this allowed more space behind the carburetors for the airbox
Plenum chamber
A plenum chamber is a pressurised housing containing a gas or fluid at positive pressure . One function of the plenum can be to equalise pressure for more even distribution, because of irregular supply or demand...

; and (iii) it gave an attractive raked appearance to the motorcycle.

Isolastic system

The revolutionary part of the Commando, compared to earlier Norton models, was the award winning frame developed by former Rolls-Royce
Rolls-Royce Limited
Rolls-Royce Limited was a renowned British car and, from 1914 on, aero-engine manufacturing company founded by Charles Stewart Rolls and Henry Royce on 15 March 1906 as the result of a partnership formed in 1904....

 engineer Dr. Stefan Bauer. He believed the classic Norton 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...

 design went against all engineering principles, so Bauer designed his frame around a single 2.25 in (5.7 cm) top tube. Bauer tried to free the Commando from classic twin vibration problems, which had severely increased as the volume of the basic engine design expanded from the 500 cc of Edward Turner
Edward Turner
Edward Turner was a British motorcycle designer. He was born in Camberwell in the London Borough of Southwark, on the day King Edward VII was proclaimed King....

's 1938 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...

. He, with Norton Villiers Chief Engineer Bernard Hooper and assistant Bob Trigg, decided that the engine, gearbox and swing-arm assembly were to be bolted together and isolated from the frame by special rubber mountings.

This eliminated the extreme vibration problems that were apparent in other models in the range, as it effectively separated the driver from the engine. Named the Isolastic anti-vibration system, the system's patent document listed Hooper as the lead inventor. Although the Isolastic system did reduce vibration, maintaining the required free play in the engine mountings at the correct level was crucial to its success. Too little play brought the vibration back; too much, and the result was "very poor" handling.

Mk1 750 cc

The Norton Commando was introduced in 1967 at the Earls Court Show
Earls Court Exhibition Centre
The Earls Court Exhibition Centre is an exhibition centre, conference and event venue located in west London, United Kingdom in the Royal Borough of Kensington and Chelsea . It is the largest exhibition venue in central London. It is served by two underground stations, Earl's Court and West...

. The first production machines completed in April 1968 had bending frame problems, removed with the introduction of a new frame in January 1969. The original model, called the 'Fastback' was joined by the scrambler style 'S Type' which had a high level left-side exhaust and a 2.5 gallon petrol tank. The first Commandos had a twin-leading-shoe
Twin leading drum brake
The twin-leading-shoe brake is a type of drum brake that has two leading shoes, rather than the single leading shoe and a single trailing shoe of a single-leading shoe drum brake. A leading shoe has a self-servo effect, so an advantage of a 2LS is that it provides the maximum retardation in its...

 front drum brake.

Production of the machine was initially complex and located across different parts of England, with the engines produced in Wolverhampton
Wolverhampton
Wolverhampton is a city and metropolitan borough in the West Midlands, England. For Eurostat purposes Walsall and Wolverhampton is a NUTS 3 region and is one of five boroughs or unitary districts that comprise the "West Midlands" NUTS 2 region...

, frames in Manchester
Manchester
Manchester is a city and metropolitan borough in Greater Manchester, England. According to the Office for National Statistics, the 2010 mid-year population estimate for Manchester was 498,800. Manchester lies within one of the UK's largest metropolitan areas, the metropolitan county of Greater...

, while components and final assembly was at Burrage Grove, Plumstead
Plumstead
Plumstead is a district of south London, England, located in the London Borough of Greenwich. Plumstead is a multi cultural area with large Asian and Afro-Caribbean communities, in similarity to local areas such as Woolwich and Thamesmead...

. In late 1968 Plumstead works was subject to a Greater London Council compulsory purchase order, and closed in July 1969. With assistance of a Government subsidy, the assembly line was moved to North Way, Andover
Andover, Hampshire
Andover is a town in the English county of Hampshire. The town is on the River Anton some 18.5 miles west of the town of Basingstoke, 18.5 miles north-west of the city of Winchester and 25 miles north of the city of Southampton...

; with the Test Department in an aircraft hangar on Thruxton Airfield
Thruxton Circuit
Thruxton Circuit is a motor racing circuit located near the village of Thruxton in Hampshire, England which is used to host a number of motorsport events including British Touring Cars and Formula 3 racing....

. Frame manufacturing was transferred to Wolverhampton
Wolverhampton
Wolverhampton is a city and metropolitan borough in the West Midlands, England. For Eurostat purposes Walsall and Wolverhampton is a NUTS 3 region and is one of five boroughs or unitary districts that comprise the "West Midlands" NUTS 2 region...

, where a second production line produced about 80 complete machines each week. Components and complete engines and gearboxes were also shipped overnight, from Wolverhampton to the Andover assembly line.

The production racer, featuring an overhead valve
Overhead valve
An overhead valve engine, also informally called pushrod engine or I-head engine, is a type of piston engine that places the camshaft within the cylinder block , and uses pushrods or rods to actuate rocker arms above the cylinder...

 (OHV) tuned engine, front disk brake and was finished in bright yellow - known as the 'Yellow Peril'. In March to June 1970 the updated S called the 'Roadster' had the 750 cc OHV engine, low-level exhaust, upward angled silencers with reverse cones. September 1970 saw the introduction of the classic 'Fastback Mk2', which had alloy levers with modified stands and chain guards. The ‘Street Scrambler’ and the ‘Hi Rider’ were launched in May 1971, with the ‘Fastback Long Range’ with increased petrol tank capacity from July 1971.

The ‘Combat’ engine was introduced in January 1972 saw the appearance of the ‘Mk4 Fastback’, updated ‘Roadster’ and the ‘750 Interstate’. The ‘Combat’ delivered 65 bhp at 6500 rpm with a 10:1 compression ratio, but the stressed 750 cc twin proved extremely unreliable, with main bearing failures and broken pistons common.

The 'Combat' engine combined with quality control problems gave the company a bad reputation, which was highly covered in the press. By the middle of 1972 BSA Triumph group were in serious financial trouble. The UK Government decided to bail the company out with a financial rescue package, providing it would agree to merge with Norton Villiers. Norton Villiers Triumph
Norton Villiers Triumph
Norton Villiers Triumph was a British motorcycle manufacturer, formed by the British Government to continue the UK motorcycling industry, but the company eventually failed.-Formation:...

 was duly formed and the new company got off to a shaky start.

The last of the 750 series, the MkV was produced from November 1972 to mid-1973 as a 1973 model and featured improved crank bearings and the standard grind camshaft. Compression was reduced to 9.4:1.

Interpol

After some police forces expressed interest in the Commando, Neale Shilton was recruited from Triumph to produce a Commando to police specifications. The end result was the 'Interpol' machine, which sold well to police forces, both at home and abroad. The 750 cc machine was fitted with panniers, top box, fairing, radio mountings, police lights, and auxiliary equipment. (The 'Interpol' name was retained for Norton's later rotary engined Police motorcycle
Norton Interpol 2
The Interpol 2 was a Norton motorcycle. It had an air-cooled twin rotor Wankel engine.Towards the end of the production run a few machines were built with a new water-cooled version of Norton's twin-rotor Wankel engine. These machines were designated Interpol 2A...

).

1973 Mk1 850 cc

In January 1973 the ‘Mk.5 Fastback’ was launched and the ‘Long Range’ was discontinued, foreshadowing the first 850 cc machines launched in April 1973. The ‘Roadster’, ‘Hi Rider’ and the ‘Interstate’ all began to use a new 828 cc. engine, which had similar power to the 750 cc models but were less stressed.

In late 1973 redundancy notices were issued at Andover
Andover, Hampshire
Andover is a town in the English county of Hampshire. The town is on the River Anton some 18.5 miles west of the town of Basingstoke, 18.5 miles north-west of the city of Winchester and 25 miles north of the city of Southampton...

, followed by a sit-in at the works. The Conservative Government withdrew the subsidy in early 1974, restored by the Labour party post the general election. NVT resultantly decided to concentrate production of the Commando at Wolverhampton and Small Heath, causing unrest at Meriden which resulted in a workers’ sit in and stopping production at Small Heath. By the end of 1974 NVT had lost over £3 million.

However, the company still managed to produce new Commando models, with 1974 seeing the release of the Roadster based ‘JPN Replica’ and the ‘Mk.2a Interstate’.

Mk3 850 cc

The 850 cc MK3 Commando was launched in March 1975 and for the first time was fitted with an "electric starter" - better described as electric "assister", as it would soon drain the battery. The range of models was reduced to just two machines, the ‘Mk.3 Interstate’ and the ‘Roadster’, both with a left side gear change an a right foot brake to comply with United States vehicle regulations, and a rear disk brake. The specification remained unchanged until October 1977 when the last machines were made, although few 'Roadster's were made in the end due to the higher cash sales value of the Interstate.

In 1975 the Industry Minister recalled a loan for £4 million and refused to renew the company’s export credits. The company then went into receivership and redundancies were announced for all of the staff at the various sites. At Wolverhampton an action committee was formed in an effort to continue production and develop the ‘Wulf’ engine - but the works was closed anyway.

NVT was saved when the Small Heath/Meriden part of the company was subsidised by Industry Secretary Tony Benn
Tony Benn
Anthony Neil Wedgwood "Tony" Benn, PC is a British Labour Party politician and a former MP and Cabinet Minister.His successful campaign to renounce his hereditary peerage was instrumental in the creation of the Peerage Act 1963...

 as Industry Secretary, but this did not include Commando production. Ironically, the new company bought the gates from the demolished Tong Castle
Tong Castle
Tong Castle was a very large mostly Gothic country house in Shropshire, set within a park landscaped by Capability Brown, on the site of a medieval castle of the same name....

 and erected them at the works entrance in Marston Road.

Racing

Right from its 1967 beginnings the Commando took part in racing events. After successes in 1969 by dealer entered machines like Paul Smart's second and Mick Andrew's 4th places in the 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...

 Production class and a win in the Hutchinson 100 Production Class by Mick Andrew on the Gus Kuhn entered Commando and 4th by Peter Williams' Arter Bros machine, the company decided to produce a racing model - hence the developed S and "Yellow Peril" models.

In the early 1970s, with sponsorship from John Player Special cigarette
Cigarette
A cigarette is a small roll of finely cut tobacco leaves wrapped in a cylinder of thin paper for smoking. The cigarette is ignited at one end and allowed to smoulder; its smoke is inhaled from the other end, which is held in or to the mouth and in some cases a cigarette holder may be used as well...

s, Norton went factory racing. The new race bikes were based on the Commando, and in 1973 Peter Williams
Peter Williams (motorcyclist)
Peter Williams is a former Grand Prix motorcycle road racer. His father was Jack Williams who ran the Associated Motor Cycles race department. Peter trained in mechanical engineering and introduced many innovations that are commonplace on today's road bikes, such as alloy wheels and disk brakes...

 won the Formula 750 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...

 on a monocoque
Monocoque
Monocoque is a construction technique that supports structural load by using an object's external skin, as opposed to using an internal frame or truss that is then covered with a non-load-bearing skin or coachwork...

-framed "JPS Norton" special. Shortly afterward there was a merger of Norton Villiers with BSA-Triumph
Triumph Motorcycles
Triumph Engineering Co Ltd was a British motorcycle manufacturing company, based originally in Coventry and then in Solihull at 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...

 (to form NVT
Norton Villiers Triumph
Norton Villiers Triumph was a British motorcycle manufacturer, formed by the British Government to continue the UK motorcycling industry, but the company eventually failed.-Formation:...

). This event led the factory to abandon racing; and a Norton factory team did not resume racing until the Wankel-engined Nortons of the 1980s.

Commando revival

In light of its "last of the classic British twins" tag, and the fact that many of the trade marks were disputed and patents expired, a number of new Norton companies began to emerge. These were based on production of new parts sourced from various manufacturers, and the legal battle over the Norton name between Germany (whose Norton was based on the Rotax 650 cc engine that powers the smaller BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...

 motorcycles), Canada and North America. Many used the Commando name for their lead model, or included the prospect of a Commando twin at a later date.

However, the most interesting development for original Commando fans was the development of re-manufactured original motorcycles. These mainly came from Norvil in the UK and two companies in the United States, Colorado Norton Works and Kenny Dreer's Vintage Rebuilds based in Portland, Oregon
Portland, Oregon
Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...

. From 1995 onwards Vintage Rebuilds began restoring vintage British and Italian motorcycles, with Dreer showing a "new" Commando based Norton VR880 Sprint Special in 1999 with newly cast and manufactured parts, but using a bored out 880 cc twin engine with some modern developments. Kenny Dreer progressed from restoring and upgrading Norton Commandos to producing whole machines. He modernised the design and in the early 2000s went into series production of the Commando 961 SS
Norton 961 Commando
The Norton 961/SS Commando is a motorcycle that was produced by Norton Motorcycles, the Oregon based company that bought the rights to the Norton brand name. Owner Kenny Dreer progressed from restoring and upgrading Norton Commandos to producing whole machines. He modernised the design and in the...

, which combined traditional Norton cafe racer
Café racer
A café racer is a type of motorcycle as well as a type of motorcyclist. Both meanings have their roots in the 1960s British counterculture group the Rockers, or the Ton-up boys, although they were also common in Italy, Germany, and other European countries...

 styling with new technology including carbon fibre wheels to reduce weight and a chro-moly tubular steel frame. Dreer was forced to suspend production in April 2006 following funding problems.

New Donington Commando

UK businessman Stuart Garner, owner of Norton Racing Ltd, acquired the rights to the Norton Commando brand. His company, Norton Motorcycles (UK) Ltd, established a new factory at Donington Park
Donington Park
Donington Park is a motorsport circuit near Castle Donington in Leicestershire, England.Originally part of the Donington Hall estate, it was created as a racing circuit during the pre-war period when the German Silver Arrows were battling for the European Championship...

 Derbyshire
Derbyshire
Derbyshire is a county in the East Midlands of England. A substantial portion of the Peak District National Park lies within Derbyshire. The northern part of Derbyshire overlaps with the Pennines, a famous chain of hills and mountains. The county contains within its boundary of approx...

 to manufacture a new Commando model, designed by Simon Skinner. There are three models in the new Commando range: a limited edition of 200 Commando 961 SEs, a Cafe Racer and a Sport model. In March 2010 Norton shipped the first new Norton Commando for over 30 years; and by mid-April 2010 the Company was shipping 5-10 new machines per week. The engine is a 961cc fuel-injected
Fuel injection
Fuel injection is a system for admitting fuel into an internal combustion engine. It has become the primary fuel delivery system used in automotive petrol engines, having almost completely replaced carburetors in the late 1980s....

 air-cooled ohv 270° parallel twin that produces 79 hp(59 kW). The short-stroke engine is oversquare, with a 88 x 79mm bore and stroke. At the bike's front are inverted (USD) forks and twin disc brakes. The engine (rather like the BSA A7
BSA A7
The BSA A7 was a British motorcycle manufactured by Birmingham Small Arms Company at their factory in Armoury Road, Small Heath, Birmingham in 1946. There were actually two versions of the A7, the original 495cc version and an improved 497cc version launched in 1950...

) is "semi-pre-unit", in that the 5-speed gearbox is a separate casting, but is bolted directly to the primary chaincase. Some styling is reminiscent of the original Norton Commando, especially the engine and petrol tank. The new Norton has received favourable press reviews
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