Page 17. 1921 ABC Flat Twin 398cc ‘Sopwith Machine’ SOLD

1921 ABC Flat Twin 398cc ‘Sopwith Machine’


Founded by Granville Bradshaw, All British Cycles (ABC) began producing motorcycles in 1913. Their designs were noted for innovative features, such as a transversely-mounted flat twin-cylinder engine in 1918, five years before BMW adopted the design.

Founder Granville Bradshaw also designed a unit-construction horizontally-opposed flat twin for Sopwith Aircraft in 1914. The company had a long association with Sopwith as innovators of several designs for the latter.


The innovative 398cc ‘Sopwith Machine’ caused a sensation at the 1919 Motor Cycle Show, with front and rear leaf springs, internal front and rear expanding brakes and cradle frame, footboards and leg shields. Some 2200 were made, of which only about 10% survive, a remarkably high number for a vintage motorcycle. Various types of valve gear conversion sets were made available later, and speedometers, electric lighting sets and sidecar outfits were optional extras.

From 1920 to 1924 the machine was also made under licence in France by Gnome et Rhone. Some 3000 French models were manufactured but relatively few seem to have survived.

ABC also developed a 123cc motor scooter, the Skootamota, in 1919, but by the early 1920s, production problems led to escalating costs, and in 1923 the company stopped manufacturing.


This 1921 ABC motorcycle is a superb example. It was restored about 10 years ago, with the engine totally stripped and rebuilt with new parts. The current owner has added new exhausts; replaced the handlebars with the correct flat racing bars; numerous parts have been nickelled; wheels have been rebuilt; new tyres; rebuilt mag; period claxton horn. The electric lights are not wired up.


The bike starts easily and runs well, though it would benefit from a tune up. A new MOT will be provided on sale. It has a DVLA V5C registration document.


I hope you can see all you need from these photos. But if you have any questions, require larger resolution photos, or wish to view, please email or phone me as below.



Sopwith Aviation & Engineering Co


The Sopwith Aviation Company was founded in 1912 by Thomas Octave Murdoch Sopwith, already a noted pioneer pilot. A number of the company’s designs, amongst them the Tabloid and the Gun Bus saw service at the start of the First World War, but the 1 ½ Strutter of 1916 was the company’s first major success. This was followed by the Pup and then the Sopwith Camel, of which 5,490 were built in the last two years of the war. This was a difficult aircraft, but could be very effective in the right hands, and was the most successful British fighter of the war. The Sopwith Triplane of 1916 was also highly regarded, although was produced in much smaller numbers.

The Camel was followed by the Sopwith Dolphin of 1917, another highly manoeuvrable fighter, and finally by the Sopwith Snipe. This last aircraft entered service in the last few weeks of the First World War, and remained the standard RAF fighter aircraft in the decade after the war. The Sopwith Salamander was a ground-attack aircraft developed from the Snipe, which also just managed to enter service in the last few days of the war. Sopwith also produced the Cuckoo, a purpose built torpedo-bomber which began to be delivered in September 1918.

Sopwith did not survive after the end of the war. A combination of the post-war collapse in aircraft orders and a massive tax bill forced Thomas to close down the company in September 1920.

Although the Sopwith Company had been short-lived, Sopwith himself had a long career in aviation. On 15 November 1920, the former directors of Sopwith and their chief test pilot Harry G. Hawker formed the Hawker Engineering Co Ltd, with Sopwith as Chairman. He would remain active in the aircraft industry into the 1980s, remaining Chairman of Hawker Siddeley until 1963.














By way of comparison, here’s a picture of my ABC Skootamota of the same year (which I sold to a scooter/ 3-wheeler museum in Thailand in 2008).


The ABC Skootamota, designed by Granville Bradshaw, was the first scooter which allowed the passenger to sit, so it’s considered the forerunner of the modern scooter.

It was well designed. The small wheels made it very stable. Its engine is positioned above the rear wheel, which it drives by chain, and the saddle and spacious footboard provide ample comfort for the rider. Of the various early scooters that came on the market around this time, the Skootamota was the best. It was comfortable and easy to ride. Its top speed is 15mph.

This first generation of scooters was initially marketed toward female riders. But, as you can see in the advert above, potential male customers were not ignored. I remember reading in a motorcycle magazine of the period how scathing some in the motorcycle press were of the new ideas for scooters. In particular, I recall an article about the Autoped from around 1917, where the journalist speculated about traffic jams of autopeds coming back from Brighton to London after a day out at the weekend. Of course, you had to stand on the Autoped. I rode my Autoped (sold in 1992) for only a short distance; it was quite unstable. So I can appreciate how well the Skootamota was received at its introduction in 1919, because it was so much more useable for long-distance riding, even at 15mph top speed.

The Skootamota ceased production in 1922. But the seeds were sewn …after World War 2, its concept was revised and modernists have not looked back since.






OWNER: Peter

LOCATION: Skipton, North Yorkshire, BD23, United Kingdom.

DELIVERY: is not included in this auction. The website contains details of recommended delivery services.

United Kingdom – delivery is £70 for a vintage motorcycle to most parts of England (Cornwall, Wales, Scotland extra: please email your postcode for a quote).

Europe – delivery is around €400 Germany, Austria, France, Italy, Spain, etc.

North America, Australia, New Zealand, Japan – I’ll organize shipping for you.

VEHICLE CONDITION: Vintage vehicles are wonderful beasts – but each has an individual personality and they sometimes have bad days just like you and me.
You will need basic mechanical skills (or a local mechanic) to use one on a regular basis.
2-Stroke engines – and cyclemotors in particular – are notoriously unreliable. Basic servicing is generally required if unused for even a few weeks.

These are rare vehicles whose values are not necessarily based on running order.
Unless an auction description specifically states that the vehicle is running, THE VEHICLE IS SOLD FOR RESTORATION.
I purposely understate the condition of any vintage vehicle sold on behalf of a 3rd party. I am not liable for the condition of any vehicle not owned by me.



If you have any questions about this (or any other vehicle in these BuyVintage Online Auctions),
you can contact Colin in our Customer Service Department between 9am and 7pm daily:

By Phone – (UK 0044) 07866-126469

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Published on April 26, 2008 at 3:05 pm  Leave a Comment  

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