Ron Parkinson: The man who made the Villiers fly
For many years Ron Parkinson Motorcycles was one of the leading motorcycle dealers in north Essex, but there is so much more to the man behind the shop, as Mike Meadows reveals.
What do the following off-road riders from the 1960s have in common – Dave Nicoll, Chris Horsfield, Vic Eastwood, Freddy Mayes, Brian Goss, Fluff Brown, Jim Timms, Olga Kevolos and Mick Andrews?
Well, they all rode and achieved success on bikes powered by Villiers engines, but motors that were enhanced with the flexibility and increased power of a Parkinson alloy conversion, commonly known as a square barrel. Marketed under the name ‘Parkinson’ and sold by R W Parkinson Motorcycles of London Road, Marks Tey, near Colchester in Essex, these were manufactured by a separate company formed by Ron called Marks Tey Industries.
Ronald William Parkinson was born in Nottingham in 1921. There was little choice of employment in the Nottingham area in the late Thirties other than coal mining, the tobacco or textile industries, or service. Ron, being a very smart upright young man, chose the latter and became a butler. However, very soon upon the outbreak of the Second World War, he joined the RAF. Initially serving some time as a dispatch rider, he then trained as a mechanic servicing motor torpedo boats. This duty brought him to the coast of East Anglia where he stayed after the war. In the early 1950s he came to the Colchester area where he made his home, met and married Joan and brought up his three children.
The early days
In 1953 Ron took over the premises of an old fish shop in London
Road (then the old A12) in Marks
Tey and, with a few pounds in his pocket and a couple of second-hand motorcycles, he began trading.
The business soon moved to another location and then expanded into a mill premises next door. Now the site is a block of flats located close to the Bungalow Diner which has been used as a venue for the Pre-65 Motocross Club AGM in the past and is probably well-known to many of you.
Over the years, the business was an agent for AMC, BSA, Cotton, Excelsior, Norton, and Triumph motorcycles, Lambretta scooters, Raleigh mopeds, Canterbury sidecars, Villiers engines and Reliant three-wheeler cars.
Second company
In 1961, and after much planning, the second company was formed and traded as Marks Tey Industries at a separate nearby site. MTI was formed to produce a range of aftermarket engine parts, alloy barrel conversions for the Villiers engine and complete racing engines. Ron headed the MTI team, assisted by Arthur Clough who focused on detail design and made the patterns, and Cecil Claridge who made the tooling and took responsibility for the machining.
It produced a range of retrofit competition engines and engine parts for, and compatible with, the standard Villiers single 197cc 9E and 250cc
34A and later 36A engines. The target market for this product were private owners of competition scrambles and trials motorcycles; original equipment manufacturers of new machines (except Greeves which had its own in-house product) and owners of the Villiers-engined Class 210 go-kart.
In order to be competitive, the 250cc engine had to deliver in excess of 24bhp at 6000 revs per minute and 20bhp for the 197cc. Additionally, this power range had to be sustained for at least the duration of a long race of at least 40 minutes. Two-strokes at this time with cast iron cylinders could lose up to 30% of full power in a race. Then, of course, the engine had to be reliable and rugged.
To deliver power, close bore clearances are essential and to sustain power heat dissipation is critically important. Therefore, the cylinder was made of a material with a similar coefficient of expansion to the piston, i.e. aluminum alloy LM 14 – for the time it was very large at 500 sq in total area.
To achieve this, the footprint was rectangular and very similar externally to the Ehrlich EMC split single. To assist heat transfer further, no liner was deployed. Instead, a hard chrome deposit was applied directly to the cylinder and then ground to size. This process was very state-of-the-art for the time and all modern racing and sports motorcycles now use a similar technique, using a ceramic instead of hard chrome.
The cylinder head got even hotter than the cylinder and was almost as large, having a surface area of 400 sq in. To maximise heat transfer to the cylinder, no head gasket was used. The racing engines had a high compression squish head (again now commonplace), whilst the trials version – where torque is more important – had a low compression head. Both versions used a central spark plug.
The piston used was made of a very high-grade low coefficient expansion aluminium silicon alloy, the 250 being forged and the lower production volume 197s cast. Mortality was higher with the cast pistons. To maximise the primary or crankcase compression, a very low crown height was used and was dimensionally the same as a Vale Onslow piston. This design also reduced the weight of the piston which decreased the out of balance forces and stress, in particular on the big end and main crankshaft bearings.
The cylinder runs hot naturally, but to achieve a good thermal efficiency the incoming charge must be kept cool. Therefore, to reduce heat transfer to the crankcase, a quarter-inch Tufnol heat-insulating shield was fitted. The crankcase was also finned to dissipate any residual heat transferred and to improve rigidity. In order to achieve a good volumetric efficiency, the crankcase was designed to have a very high compression ratio for the time of 1.5:1. This was assisted by the use of full circle internal flywheels with an oval connecting rod supplied by Alpha Bearings, all now again industry standard. The whole assembly was very stiff to prevent the crankshaft twisting.
The maximum size carburettor available at the time, a 389 Amal Monobloc, 13/16in or 30mm, was fitted with the exhaust being 1¾in or 45mm. The were two exhaust options, centre port for twin down tube bikes like the Cotton Cougar, or side port for single down tube machines.
Industrial espionage
The cylinder conversion was launched on October 1961, followed by the crankcases in January
1963. Advertising information was produced for the conversion and appeared regularly in the motorcycle press and programmes of motorcycle events such as scrambles and grasstrack meetings; separate advertising literature for the crankcases was produced.
As a young teenager I was mystified as to why the only two Villiers racing conversions available were both made in Colchester. It was only when Ron Parkinson told me the story back in 1992 that I at last found out why.
During the development phase, and way before the initial product launch release to the press in 1961, an enthusiastic but not very astute or commercially aware Arthur Clough unintentionally leaked the product plans to another local motorcycle business competitor. Ron, understandably, was absolutely furious.
The story goes that Mr Derek Brown, the owner of Cromwell Motors in Maldon Road, Colchester, knew that Ron was up to something special.
So he invited Arthur out to a public house one evening and, after far too many free drinks, got him to tell all.
Brown then decided that the market was big enough for two manufacturers and, shortly after the Parkinson product launch, he announced his own similar square alloy cylinder conversion. The conversion was called the Marcelle and he was able to secure the exclusive use by DOT. Although the DOT works riders had some success, it was generally accepted that the product was inferior to the Parkinson. The fact that both conversions were made in Colchester has led to a great deal of confusion within the classic motorcycle press of today, together with the real origins of how the name of Marcelle came about. Recently I even read that the Marcelle conversion was designed in France!
The good days
The local and national advertising produced a steady stream of riders wishing to ‘upgrade’ their now outdated machines, although most conversions were sold direct to original equipment manufacturers. With limited manufacturing resources, the success of the Parkinson cylinder conversion put back the launch of the crankcase product.
Marcelle may have secured DOT exclusively but the Parkinson conversion enabled motocross and trials motorcycle firms, particularly Cotton, Francis-Barnett and James, to remain competitive against the all-conquering Essex-based Greeves concern until Villiers at long last got its act together and produced the Starmaker engine. Other smaller motorcycle OEMs supplied with conversions included Butler, Elstar, Firefly and Scorpion.
By the time production ceased, well over 400 conversion kits had been sold, many going for export, mainly to Australia where Cotton of Gloucester had a good market share. The Cotton Cougar was the most
successful and prolific machine using the Parkinson conversion; typical of Cotton, it had a fully triangulated frame and production ran for four years, from 1962 to 1966. Although the crankcase assembly proved costly to make, over 22 complete engines were made.
Success within scramble and trails events is well documented, but the Parkinson conversion achieved success in other forms of racing. Tig Perry, the excellent grasstrack racer who started the Antig grasstrack motorcycle manufacturing company, used a Parkinson conversion fitted to a Villiers engine in one of his own bikes in 1965 (and possibly earlier seasons). I myself currently have a Parkinson conversion fitted to my Elstar grasstrack bike.
Success also came within the Go Kart 210 class. Purchasing a Parkinson conversion saved owners hours of meticulous preparation and reworking of the old 9E cast iron cylinder much improved reliability as well.
By 1967 the Villiers Manufacturing Company was part of the
Manganese Bronze group that also owned Norton and AMC motorcycles. In an ill-fated attempt to eliminate the competition, a group policy decision was made not to sell engines to manufacturers outside of the group. The supply of Villiers A Series and Starmaker engines dried up and firms had to source engines from abroad. This was the beginning of the end of the British two-stroke competition motorcycle industry.
With no market for the Villiers A series engine-based products and Invader Karts securing the go-kart market, a decision was taken to wind up MTI.
Other projects
The Ariel Arrow was a great bike and quite revolutionary for its time. With offset gudgeon pins in the piston the port timing was asymmetrical. But, just like any other bike with cast iron cylinders, power loss occurred when hot. So Ron made a range of aluminium alloy barrels for the Arrow but these were a bit expensive for the average teenage rider. Sales were low but that did not deter Ron who was very taken by the Arrow engine, so he created a triple using his barrels and a special crankcase. The engine still exists in its prototype form, but lack of time, money and other business pressures prevented the engine from being developed fully.
As the British motorcycle industry began to fall apart, Ron looked elsewhere for additional revenue sources. He secured one of the first dealerships for the Japanese Kawasaki marque and developed the clothing side of the business. He financially supported a number of up-and-coming young riders in road racing and his pick-up truck would often been seen at Snetterton meetings. Ron became president of the Eastern Sporting Sidecar Club and was a founder member of the Colchester Waterski Club, while he and Joan also supported a number of local charities.
Friendship
I first met Ron in 1963 when I was only 16 years of age and just about to start riding in scrambles, on what else but a Greeves Hawkstone fitted with a Parkinson conversion. I needed that essential piece of riding gear for the period, a body belt, so off I set to his shop with my friend, Nigel Dodd (remember Nigel’s articles on sprinting a few issues ago?), two up on my little 197cc Sun Challenger. Of course, always being taught to treat elders with absolute respect – and remember this was 1963 – I could not believe I had met the man himself.
The makes of bikes I subsequently owned were not supported by Ron’s shop so I used other local dealers, but fast forward nearly 25 years and I built up another Greeves for use in Pre-65 motocross which was fitted with a Parkinson barrel. I called into the shop to see if Ron was there. He was, and I asked if I could spend some time with him at his convenience to discuss an MTI story for the Greeves Riders’ Association newsletter, ‘Leading Link.’ Ron declined, saying it was all in the past, but he did take my details.
I think I tried once more at the shop and then, out of the blue one evening after Ron had retired from the business, he rang and asked if I would like to come over to see him at his home. We spent an evening going through the whole story and it was published in Leading Link back in 1993 and was again reprinted in August 2016 together with a subsequent update from me.
Obviously having to make more than one visit, and getting Ron to approve the final proof, we progressively got to know each other well and ended up friends. I stayed in contact and made regular visits to see him.
Ron had actually formally retired from the business in 1986 and during his retirement spent many hours painting landscapes in oils and acrylic, model boat building to a very high standard and restoring the odd vintage motorcycle.
One day I asked Ron if he was aware that the cylinders for the two prototype single-cylinder
Alpha rotary valve engines were remarkably like his own. His reply was very simple; “We cast them for Alpha”. Ron used Alpha full circle cranks for his engines and had a good business relationship with Frank Cuttler up in Dudley.
Ron made 22 complete engines using Villiers magneto, clutch and gearbox and an Alpha crank. I knew of one engine located in Ipswich still owned by a very capable scrambles rider from the 1960s, but then in 1995 a friend told me about an unusual Villiers engine at a Chelmsford bike breakers. I rushed over to the shop during my lunch break – and there was a complete Parkinson engine.
The owner had recently died and had used the engine in a grasstrack bike. Although the rolling chassis had been sold, the engine remained hidden beneath a work bench. I immediately purchased the engine and rang Ron that evening to ask if I could come over to see him the following Saturday as I had something to show him, but I wouldn’t tell him what it was!
A pleasant surprise
Ron by this time was not in the best of health and was restricted to a wheelchair. On the Saturday I set the engine up on a work bench in his garage and when he came in he couldn’t believe that one of his engines had survived. Needless to say, he was very pleased and took many photographs.
That same day Ron gave me the original mould for one half of the crankcase, unfortunately the other half had gone missing. The mould was simply a modified standard Villiers crankcase with fins and additional webbing just glued on. Flat faces also had additional packing to take into consideration casting shrinkage. Some years later I was lucky enough to spot another pair of crankcases at a Kempton autojumble and immediately made another purchase.
Thus, at least three of the 22 engines still exist and I still plan to fit at least one of my engines to a James M25R Cotswold scrambler currently held up in my bike restoration queue.
Celebrating Ron
Sadly, after a long illness, Ron died in 1996 and is buried in the churchyard in Copford, Essex. Prior to his death I gave two relatively informal talks on his achievements to the local Rotary Club and the Maldon section of the VMCC. Within Colchester there had always been a well supported Engineering Society and after Ron had passed away I had the privilege of presenting its main annual talk at my old engineering college.
No pressure, as one of the previous speakers had been
Graham Hill, twice Formula 1 champion, and I remember clearly going to see him at the same college back in the 1960s. I was very fortunate to have the support of friends who lent me additional photograph material, and of Ron’s family.
The lecture theatre was overflowing with standing room only and it all turned out rather well. Ron’s family all came along, his daughter lent me the Arrow triple to display and I brought the Parkinson engine. The audience was a mixture of engineers from the society; current customers from the shop that had no idea of the founder’s past achievements and a whole group of ex-trials and scramble riders from the 1960s. It was a brilliant celebration of Ron’s engineering achievements, his legacy to the classic motorcycle movement and his business vision.
By that time R W Parkinson Motorcycles was a main agent for Kawasaki, Aprilia and Ducati. The shop moved to a more central Colchester location and ceased trading a few years later.
However, if you see a Parkinson conversion at an autojumble, or on eBay, there should be a ‘buyer be aware’ sticker on it! Remember, it was designed with a piston having a crown height a quarter inch lower than a standard Villiers piston. If you just fit a standard Villiers piston it will pop out of the top of the cylinder by the same quarter inch and, if you leave the Tufnol heat shield off, then by half an inch.
It gets even worse if the conversion is a 197cc 9E to 250 designed for the 5¼-inch con rod… The good news is that no machining is required other than making up cylinder base packing in progressive quarter-inch steps.
I boldly asked Ron one day, why go to all the bother making a specific 9E to 250cc conversion barrel? Why not just do away with the heat shield? I was firmly put in my place and told that the heat shield was an integral element of the design and no degree of product rationalisation was acceptable.
Engineering is a profession where great engineers can leave an equally great impression on society. Although Ron has passed away, he has left a real legacy for those of us interested in classic off-road racing motorcycles. Parkinson conversions are both rare and much sought after by enthusiasts restoring classic motocross and trials motorcycles, particularly James and Cotton, to show standard.
Sadly, fewer and fewer Parkinson conversions and engines can now be seen in Pre-65 trials and motocross, but there are a few still running.
Interestingly, a few years ago I had a phone call from Matthew Brown, the son of Derek Brown, who sold the Marcelle conversion. He was very interested in the whole story of how the Marcelle and Parkinson conversions came about in Colchester and is undertaking research from a Cromwell Motors perspective. I know that Matthew has purchased a Marcelle barrel and hopes to build a replica one day of the last complete Marcelle scrambler built, similar to the one raced by Pat Lamper. But that is another completely different story…