Click here for a
"Dunstall 810 Story"

We are looking for pictures, stories and resources to be published here.
Please send them to:
rasprey@gmail.com

** 810 Dunstall for sale in Pflugerville, Texas - Click here for details. **


Dunstall Power

 

 An example of a Dunstall Norton

 

Chapter One - The Early Years (1950's)

 

The first year after he left school, Paul Dunstall helped his father Arnold to build a dream bungalow on the slopes of a wooden hill in Erith, overlooking the Thames estuary. As a reward, Paul was taken into the family business selling scooters and mopeds. While his father sold 30 to 40 scooters a week, Paul managed a smaller shop up the road specialising in mopeds and light scooters.

Paul first got involved with motorcycles in 1955 when, at the age of 16, he obtained his first machine. It was an old MAC Velocette 350, which was fun to ride, but needed lots of care and attention to keep it going. Within a year, the old 350 has been replaced with a new 600cc Norton Dominator 99 which he immediately began modifying to achieve better performance.

In 1957, at the age of 18, Paul started his racing career. Needless to say, all the parts necessary to convert a road going Dominator into a competitive racer were not available as everybody preferred the Manx Norton single cylinder engine to the Dominator twin cylinder engine. Therefore all the parts had to be made and fitted by Paul. He took the silencers off and fitted a Manx gearbox and wheels. He also carefully prepared the engine incorporating his own ideas for improving the performance and reliability up to racing standards. He balanced the crankshaft and carefully re-assembled the engine. Other improvements over time included fitting the engine into a genuine Manx Norton Chassis.

Paul racing career was centred on Brands Hatch. Even though he was up against the more popular Manx Norton, he came 3rd in his first clubman's race at Thruxton, followed by two outright wins at Brands Hatch. After this he graduated to the expert class where he gained 3rd and 4th places in events at Brands Hatch, Cadwell Park, Silverstone, and Crystal Palace. It was obvious that the work he had done to convert his stock Dominator into a racer had been very successful, the machine ended up faster than many of the more conventional racing machines around at that time.

By the end of 1959, Paul had retired from racing simply because he found that he received greater satisfaction from preparing and modifying machines than he did from racing them. He had also got married to his wife Lynn. It was during this time Paul got to know a fellow racer Fred Neville well, and when Fred asked if Paul would build a Dominator for him to race, Paul was only too pleased to say yes. The bike was built in the scooter shop between working on customer's scooters. His Dominator kept on winning and in time it brought a few Norton owners into the shop.

Chapter Two - The Age Of The Café Racer (1960's)

To allow a narrow fairing to be used on the Dominator, Paul had designed some swept-back exhaust pipes. He had a couple of spare sets made and hung them up in the back of the scooter shop. A few people who had seen Paul on his Dominator called by the shop, saw them and wanted to buy them. He ordered another half dozen exhausts, which were sold before they were even finished. So he ordered another 50 sets, sold those and it snowballed from there.

No one but Paul had successfully raced a Dominator and the parts he was making for racing could be sold to the general public. He had the market to himself. The swept back pipes caught on in 1960. Clip-on handlebars, Gold Star pattern silencers, headlamp brackets, rear-set footrests, glass-fibre and light alloy tanks all followed in rapid succession. He could scarcely believe there such a tremendous demand. His first catalogue was published in 1961 and from then the business mushroomed at an incredible rate.

In January 1962, when Norton sold out at Bracebridge Street, Birmingham, Paul bought most of the experimental Domiracer twin engines and development bits and pieces that had been developed for the factory race team. This included the actual machine raced by Australian Tom Phillips to a magnificent third place in the 1961 Senior TT. From then on he was in business with his Domiracer line of speed equipment for engines, in addition to the tanks, seats and fairings for face-lifting the motorcycle parts. Dunstall also raced the ex-works bike that had been ridden by Tom Phillips. In fact Tom Phillips himself rode the machine for the Dunstall team for six races during the 1963 season. He achieved two wins, three spills and one breakdown.

Tragedy struck the Dunstall-Neville partnership when Fred was fatally injured while leading the Senior Manx Grand prix in 1961. His successor to ride the new famous Dunstall Domiracer was Dave Downer. Paul signed up the promising Dave Downer at the end of 1962 to race for him during the 1963 season. In May 1963, Dave Downer was to meet his death at Brands Hatch whilst duelling for the lead in the main event of the day with the "King of Brands" Derek Minter. Following Downers death, Manxman Syd Mizen took over the riding duties while Paul developed the road going version of the Domiracer.

In 1964, the bottom fell out of the scooter and moped market almost overnight. To take up some of the 'slack' Paul took on the Norton agency. He also moved from the smaller shop to the slightly larger one in Well Hall Road, Eltham. After expanding the range of his own bits, it was a short step to build fully customised bikes to buyer's specification. Meantime, Paul continued to sponsor road racing with a string of riders who included over the years Dave Downer, Joe Dunphy, Syd Mizen, Rex Butcher, Chris Conn, Derek Minter, Peter Williams, Griff Jenkins, Ray Pickrell, Tom Phillips, Dave Degans and Ken Redfern.

For the 1964 race season, Syd Mizen rode the 500c Domiracer. Colin Seeley join the team when he fitted a 650 Domiracer engine in his sidecar outfit. Dave Degans joined the team half way through the season and continued into the 1965 season. Colin Seeley also continued to use 650 and 750cc Domiracer engines in his outfit.

Paul's racing experience with the Dominator had taught him a lot about the Norton engine and he was soon looking for ways to improve performance. Although he had no formal engineering qualifications, he felt that experience was his best teacher. He experimented with different cam profiles, strengthened main bearings and altered combustion chamber shapes. Each component or modification made was tested on the racers, and if successful, was immediately considered for inclusion in the specification of roadsters available to the public.

In 1966, Paul started building complete machines. They were based on stock machines, which were stripped and rebuilt using Dunstall parts, equipment, and know how. You cannot define a Dunstall machine just like that. Given a basic Dominator engine, you can add a wide range of finished products such as seats, tanks, and fairings. You can change the gearing, or replace heavy iron or steel parts with lightweight alloy versions. The descriptions of the Dunstall machines have been gathered from magazine reviews and catalogue descriptions. The 1966 catalogue listed machines based on the Norton 88 SS, 650 SS or 750 Atlas, the Triumph 500cc and 650cc machines and the B.S.A. 500cc and 650cc twins.

His 1967 catalogue listed the same three ranges of bikes. The basic Norton machines boasted new wheels, front brake, mudguards, tank, seat, handlebars, footrests, exhausts and silencers and many original parts chromed. This cost £45 above the list price. For an additional £30, you could add a tuned engine. This included the following modifications: paired large bore carburettors, enlarged and polished ports, finned alloy induction spacers, lightened and polished rockers, pressure rocker oil feed kit, lightened cam followers, special high compression pistons, bronze valve guides, double speed oil pump and larger engine sprocket. The Triumph and BSA models had external changes but no engine modifications. By 1967, Paul had produced some 300 fully customised machines.

At the same time that this was going on, Paul was at the centre of a controversy over the 'standard machine' definition for production racing. Dunstall Dominators were being raced in 'stock' events and Paul was obliquely accused of nudging the would-be amateur sport of production racing in the cut throat world of 'pure' racing competition. Paul's answer to these charges was that during 1966, the UK tax authorities classified Dunstall Motorcycles as a motorcycle manufacturer in its own right. They insisted that the Dunstall produced Dominators were more Dunstall than Norton. In addition the Auto-Cycle Union, governing body of the motor racing sport in Britain, had homologated the Dunstall Dominators as a marque for the production machine event at the 1967 Isle of Man TT.

Also during 1967 Paul decided to pit his 750 Dominator against the clock at Monza. With Rex Butcher as pilot, the Dunstall Dominator gained the 1-hour, 10-kilometre, 100-kilometre records at an average speed of 126.7 mph. The highest speeds on the straights were over 140 mph. Paul sponsored a racing team equipped with 500, 650 and 750cc Norton twins designed to test production and prototype Dunstall parts. Road going Dunstalls were also raced in production machine competitions. The claim that they shared the same specification was proved on the Isle of Man when speed trap recorded a Dunstall 'factory' Dominator at 132 mph while other riders with stock machines were nudging 130 mph.

The bulk of the trade with the US at this time was for engine tuning parts. This was contrast with the rapidly expanding Swedish market that was similar to the home market. Reg Curley was carrying out the glass-fibre work and most of the light alloy parts were being made in Italy. This was mainly due to the high cost of labour at that time in the UK.

By the 1968 catalogue, the B.S.A machine had been dropped and it listed just the 750 Atlas model and a choice of Triumph T100 or T120 machines. The Norton model was based on the Monza record-winning machine. The engine mods included a Dunstall designed camshaft, a pair of monobolc 1" carbs, enlarged, reshaped and polished ports, lightened and polished rockers and cam followers, bronze valve guides, high compression pistons, double speed oil pump, and pressure feed to rockers. For the first time, the machine featured bolt-on twin hydraulic discs. The cost was £558 15s 2d including purchase tax.

In June 1968, Paul introduced a machine aimed specifically at the American market. This was the Dunstall American. It was a Dunstall Norton 750 fitted with high rise handlebars, high level exhaust pipes and a twin leading shoe brake instead of the a twin disc unit to distinguish it from his UK models. A lower (4.53:1) overall gear ratio was fitted. The buyer could choose forward or rear mounted footrests and a 4.00-18 or 3.50-19 rear tire. The machine could not be bought in the US, instead it had to be shipped in from the UK meaning that the buyer also had to pay airfreight charges and import duty on top of the cost of the machine.

Ray Pickrell was the rider of the super fast 750 Dunstall Domiracer which took 17 1sts during 1968 including the Isle of Man production TT where he set a lap record of 99.39 mph and a new race record. The other wins during 1968 included the Hutchinson 100 Production Race, the Evening News International; the Master of Mallory where a new lap record was set, and the King of Brands. First places were also obtained at Oulton Park, Cadwell Park, Thruxton, Crystal Palace and Snetterton.

Despite the successes Ray Pickrell had during the 1968 session, he was fighting hard all the while to stave off the better handling 50 BHP singles. To combat this Paul developed a radically new frame. Eddie Robinson designed the frame which was designed to offer a lower frontal area to the wind as well containing distortion from the big engines (72 BHP) overwhelming torque in an area of the chassis that doesn't affect handling. This was accomplished by basing the frame on a 3-in, 16-gauge spine tube, which also served as the oil tank, plus 1-in, 17-gauge support tubes. The torque reaction was contained within the engine plate and swinging arm assembly. A five-point rear engine mounting instead of the normal three-point fixture was used to do this successfully. The swinging arm pivot was unusual in that it pivoted though the 3-in centre tube as well as the two outside pivots. The winging arm spindle was an important frame member. The concept of the spine frame resembled the design of some American built dragsters of the time.

The engine and gearbox were further forward and lower than would be possible with a conventional lowboy frame improving weight distribution and lowering the centre of gravity. Dry weight was down to 306 lbs. Due to the lowness of the engine and therefore carburettor float level; two side panel tanks could be used to carry fuel 7-in lower than normal. Total fuel capacity was 2.5 gallons giving a maximum range of 75 miles. The 1969 season started well with a win at Brands Hatch. Pickrell then tried the new frame at Mallory Park where he came in third, missing first place through a missed gear change. The new machine went on to gain firsts at Crystal Palace and Thruxton and a 3rd at Snetterton.

1968 also saw the inclusion of the first parts for Japanese machines in the Dunstall catalogue. These included a 3½-gallon glass-fibre tank for the Honda CB72, CB77 and CB450. There was also a racing seat. These did not sell well and were dropped from the 1969 catalogue.

In April 1969, Paul added to his range of Norton Machines with a 750cc conversion to the 650cc Triumph. It used the existing cylinder head but with a different gasket, rings, gudgeon pins, circlips, 10:1 Hepolite pistons and light alloy barrel with lip-flanged steel liners. The Bore/Stroke was 82 by 75.5 mm yielding 740cc. A 0.020-in overbore gave 750cc and a 0.040-in overbore opened it up to 760cc. The 1969 catalogue featured an expanded range. It still included the 750 Triumph and the Dunstall Norton Sprint (Atlas), but also included a Dunstall Norton Export 750 based on the Atlas but designed as a racer with a top speed of 130 mph, and for the first time, the Dunstall Norton Commando. This had similar engine modifications to the Atlas versions and was fitted with twin hydraulic disks, a balanced exhaust system with 'Decibel' silencers, rear-mounted footrests, a 4 gallon glass-fibre tank and a new dual seat which replaced the Norton version. The machine also boasted a glass-fibre GT fairing and front mudguard, alloy top yoke and wheel rims.

Chapter Three - The End of an Era (1970's)

In the spring of 1970, the Dunstall organisation moved to the Greater London Council's industrial estate at Thamesmead. It was built on reclaimed marshland on the south bank of the river Thames. The range of machine on offer had also changed significantly. The old Atlas based machines were replaced with new Commando based versions. The range now consisted of the Sprint and Export models as before, but also included a Grand Tourer with panniers and bulkier touring fairing. The Tourer had the same engine treatment as the other machines including extensive modification of the head and ports, 1/8-in larger intake valves, high compression pistons, 32mm carburettors and many other refinements. The horsepower was rated at 68 BHP at 7,000 rpm. Also available was a six-speed gearbox with a higher top gear enabling the Dunstall Norton to achieve a top speed of 133 mph.

In the search for a more efficient exhaust system without additional noise, Dunstall worked closely with Dr Gordon Blair of Queens University Belfast, Ireland. The exhaust pipe design (two-into-one-back-into-two) was entirely Dr Blair's while one of Dr Blair's students, Sam Coates, and Paul Dunstall helped to work out the silencer design and dimensions. In addition to the new exhaust, Eddie Robinson developed a new disk brake system. This new system had three improvements over the previous Lister system. The housings, cast interegraly with each fork leg, contained the pads that gripped on stainless steel disks, rigidly attached to the hub rather than floating like the previous unit. Although stainless steel got round the problem of rust on the disk, it did not provide the same braking efficiency.

Dunstall was closely linked to the launch of the Commando. At the launch there were brochures listing custom and conversion or tuning kits. The conversion kits provided three levels of tune and resulted from collaboration with Dunstall. The first stage raised the compression ratio to 10:1 and included a pair of long tapered megaphone shaped silencers to push the speed up to 120 MPH. Stage two brought in a new camshaft, exhaust pipes, inlet tracts and inlet valves to go to 130 MPH. Stage three added a hotter camshaft, racing exhaust system with megaphone, bigger carburettors and a further 7 MPH. All the kits included various other odds and ends, but in the end, none were ever produced.

During 1970, perhaps seeing the beginning of the end, Paul became a dealer for the Honda 750. Doug Mitchenall who was with Avon fairings for a number of years designed the fairing and other glass-fibre components used on the Dunstall Honda. The range offered for the Honda were initially just body parts, but this was later to include a full range of engine parts. Paul also built a prototype Kawasaki 500cc three cylinder two-stroke engined racing machine. The last person to join the Dunstall racing team was Ken Redfern.

Paul withdrew from racing in 1971 because he wanted to concentrate on the development of the new Norton Commando roadster, which was made more difficult because it had to comply with all the US laws. 1971 also saw the launch of the Dunstall Honda CB750-4 Super Sports Roadster. It featured a modified cylinder head, reshaped and polished ports, 10:1 compression ratio, light alloy wheel rims, Dunlop K81 tyres, 3½ -gallon glass-fibre tank, GT dual seat (with locking tail compartment) and 'Ace' style handlebars.

The 1972 model range was quite small. It consisted of a Commando 750 and 810 in a Mk1 (Economy model) and Mk2 (High performance) versions. There was a wide range of Dunstall Honda equipment plus an exhaust system and high compression pistons for the Yamaha 650 XS1 and XS2. One item of interest was the Dunstall Lowboy racing frame assembly. This was based on the original factory lowboy frames, which were acquired when Paul bought the stock of factory Domiracer parts. The frame was designed to accept the Norton 750cc engine, but the 500cc or 650cc engines would also fit. The frame came with braced head stock, gusseted swinging arm pivot. Swinging arm with large diameter pivot bushes for maximum rigidity. It was fully gusseted and incorporated a special spindle adjustment. The frame came with polished dural engine plates to accept the Norton engine and gearbox, a polished chainguard assembly, polished alloy central oil tank, paired Girling suspension units, 3 1/2 gallon tank and lightweight racing seat.

In 1973, Paul started shipping complete bikes direct to dealers in the US. At first this was in kit form, and the local dealer had to assemble the machine. Later in the year, he started shipping complete machines to the dealers. He also created a wide spread dealer network in the US to market the machines and parts. Some 50% of the Dunstall machines went to the States, 20% to Scandinavia, 10% to Australia and the balance split between the home market and other countries. Machines have been exported to such places as the US, Sweden, Australia, and even Vietnam and Guam. The usual method of buying machines from abroad was to travel to the UK, pick up your new machine direct from the Dunstall shop, and then tour the UK or Europe before having your machine shipped back home. It was possible to buy parts abroad, but the cost of buying the parts and fitting them to an existing machine was often more expensive than buying a complete machine direct from Dunstall. At its peak, the company built more than 750 Dunstall Nortons in a single year.

By this time, the Dunstall business was split about half-and-half between Norton and Honda based machines. The 1973 Dunstall Honda 750 featured an exhaust and silencer system designed by Dr Gordon Blair of Queens University, Belfast, and 10.25:1 compression ratio. Other than the exhaust and pistons, the machine was mechanically standard. It did however have a partial fairing with tinted bubble shield, clip-on bars, huge glass-fibre tank and seat. The footrests were set slightly higher and further back. It also had 19" Boranni alloy wheels and Girling shock absorbers. The machine had a 19-tooth countershaft sprocket instead of the standard 18-tooth. The Honda 500-4 that had a very similar list of changes also joined the Honda 750. There was also a range of fairings for the 350, 500 and 750cc Kawasaki machines.

Also in 1973, Kawasaki approached Paul at a bike show in the US and asked if he would produce an exclusive range of custom parts for Kawasaki to sell through their network of 2,000 dealers in the US.

1974 saw the range extended again to include Dunstall Kawasaki and Yamaha machines and equipment. The Kawasaki machines had full factory backing. The Dunstall catalogue had grown so much that it was split into two parts. One part listed the parts he made for a wide range of bikes including Norton, Honda, Triumph, Yamaha, and Kawasaki. The range included conversion kits to produce a Norton 810cc (from a 750 Commando), a Honda 605cc (from a 500-4) a Honda 900cc (from a 750-4), Kawasaki 1100cc (from a 900) and a Triumph 750cc (from a 650). The other catalogue detailed the range of Dunstall machines on offer, which included an 850cc Dunstall Norton based on the new 850cc Commando.

The machines based on the 900cc Kawasaki Z1 were available in a 900cc form, or as an 1100cc expanded version. The Honda 900 produced in the same year had a glass-fibre fairing, and a glass-fibre one-piece seat and tank cover. The stock CB-750 SOHC engine has the cylinders bored by six millimetres for a total displacement of 889cc. The compression ration is raised to 10:1 and the cylinder head is modified with enlarged, reshaped and polished ports. The gear box and clutch are left stock. There is a four into 2-exhaust system feeding a pair of Dunstall Decibel silencers. The wheels are a pair of WM-2 Borrani alloy rims with 4.10 x 19 Dunlop K-81 tires. Girling rear shock absorbers, low level handle bars and rear sets complete the changes.

The 1975 Dunstall Kawasaki 1100cc Z1 followed a similar pattern to all his other Japanese based machines: - glass-fibre fairing, a glass-fibre combined seat and tank cover, lover handlebars, rear sets, 19" Borrani alloy wheels shod with Dunlop K-81 tires. The engine mods consisting of a bored out cylinder block, higher compression pistons (usually 10:1), reshaped and polished head. Some times the front brake was changed (as in this case to a pair of discs), and Girling shock absorbers fitted to the rear.

Around this time, the Dunstall moved into a pair of units in Crabtree Manorway, near Belvedere, Kent. By 1976, Dunstall were offering a tank-cover/seat unit for the Suzuki GT750, GT550 and GT380 machines. A handle bar fairing was also available for the same machines, and a sports fairing was offered for the GT250. It was in 1976 when Paul and Heron Suzuki GB launched a new Suzuki 750 in Texaco Heron Team Suzuki colours. In a complete break with tradition, Paul also offered a sports fairing for the BMW 750 and 900cc models.

The Dunstall involvement with Suzuki began in the 1975 when he customised the GT550 two-stroke triple making it into a suprisingly good and fast bike. Suzuki GB began to think that a link up with Dunstall might be useful. Paul tinkered around with few more two strokes, but by this time two strokes were becoming unfashionable. All this changed with the arrival of the Suzuki four strokes. Paul's first attempt was on the GS550 Four. Before long he went to town on the GS750 and GS1000, achieving with the latter a machine capable of 145 mph. All these machines had the factory backing.

In 1977, the Commando ceased production and Dunstall continued for a few more years producing machines based on imported Japanese machines.

Over the winter of 1978-79 did some more work on the big Suzuki and raised the top speed to 150 mph. The machine was called the GS 1000 CS or Competition Special. It was similar in specification to the other Japanese Dunstalls, but this time things were taken further: larger carburettors with new jets and bellmouth velocity stacks, the new Dunstall Power Silencers, special camshafts, and competition valve springs.

Chapter Four - The Legend Moves On (1980's)

In 1981 Paul introduced the Dunstall Suzuki GS 1000 R. It had a race tuned engine with 10.8:1 compression ration, high lift cams, oversize valves and close-ratio gearbox. The exhaust was pure Dunstall, while the wheels were by Campagnolo, the brakes by Lockheed and the rubber by Goodyear. It of course had a racing fairing and seat.

The Dunstall organization became a victim of the sharp decline in the motorcycle market at the end of the 1970's with its attendant drop on sales and profits. Paul leased out unused factory space to other businesses and finally sold the name in 1982. Paul Dunstall has since been running property companies from his home in Shoreham, Kent.