Reference: A to Z classic reference: A – Adler

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ABC Skootamota 1919-23 UK
Best of a rash of primitive scooters built in response to an expected public demand for cheap personal transport after WWI. The Granville Bradshaw designed Skootamota comprises child’s scooter-like tubular steel welded frame, engine over the rear wheel, no gears or suspension, simple controls and a pedestal seat. Spares are almost non-existent, so only buy complete examples unless you have fabrication facilities. Moderate numbers survive.

Air-cooled ioe valve (later ohv) 125cc single cylinder four-stroke, no clutch/gears, chain final drive.

ABC 1913-25 UK/France
In 1913 Granville Bradshaw designed the ABC 496 ioe flat twin, which looked similar in style to a Douglas, but with leaf spring controlled swing arm rear suspension. A handful of these early models survive. The company was reorganised in 1914 and again in 1919 but concentrated on building loose engines, spares and design. They built few complete motorcycles. After WWI Bradshaw designed for the Sopworth Aviation Company what should have been a world beater, a sophisticated transverse twin cylinder motorcycle, with rear suspension, hub brakes and optional dynamo lighting at a time when many factories were still churning out single speeders with rim brakes.

Unfortunately the valve gear was problematical and prone to shed pushrods and while lubrication was suspect, ills aggravated by cruel riders who thrashed the smooth engines mercilessly. The faults can be overcome and period engineers specialised in modifying the ABC.

Sopworth production ended in 1922 after approx 3300 complete machines were built. The French aero and motorcycle engineering company Gnome and Rhone built the ABC under licence until 1925, modifying cylinder head design and making 348cc and 493cc versions. The model has no links with either the British built Villiers powered ABC or the German 149cc version, both built in small numbers during the Twenties.

Only consider complete examples, unless you like making parts. About 10% of the total production survives. The cylinder barrels were machined from solid billet resulting in thin fragile cooling fins. Air-cooled ohv transverse twin, 398cc (French also 348cc and 493cc), four speed with chain final drive.

Aberdale 1946-49 UK
Sturdy Villiers powered pedal start autocycle built in Aberdale’s subsidiary Welsh-based Bown factory. From the 1950 season on, models were sold as the Bown. Aberdale frame number commence AAU while Bown numbers start BAU. Engine spares are available, tinware is rare. Air-cooled 98cc two-stroke single, clutch/no gears, chain final drive.

Abingdon 1903-25 UK
Built by well-known toolmakers Abingdon King-Dick, early examples used proprietary engines including MMC and Fafnir. Later models used in-house single cylinder and V-twin four-stroke units. For 1926-season machines on, models were sold as the AKD. Survivors are rare but do exist.

ABJ 1949-54 UK
AB Jackson of Birmingham built a Villiers 2F powered autocycle and a motorcycle with the Villiers 1F engine. Production ended in 1952, but a 49cc cyclemotor-like moped was made until 1954. Villiers engine spares are available but cycle parts aren’t.

Autocycle: air-cooled 98cc two-stroke single, clutch/no gears, chain final drive. Motorcycle: air-cooled 98cc two-stroke single, two speed, chain final drive.

Ace 1919-26 USA
Brothers William G and Tom Henderson of Detroit began production of the straight four cylinder Henderson in 1912. Excelsior V-twin brand (American X) owner Ignaz Schwinn from Chicago bought out the Hendersons in 1917. Following a dispute the brothers left Schwinn and William G built the first straight four Ace in 1919 with financial backing from American cycle maker Max Sladkin.

William Henderson was killed in a test accident during 1922 and famous designer Art Lemon took over development. The Ace was powerful, light and in demand but, despite full order books, production stopped in 1924. The manufacturing costings were adrift, meaning each machine had been sold at a loss and the company was heavily in debt. In 1926 the Michigan Motors Corporation made a few examples and the design was saved in 1927 when Indian bought the manufacturing rights and tooling. Despite many changes the Indian Four remained in production until 1941/42.

Achilles 1906-12 and 1951-57 Austro-Hungarian Empire, later Germany
Founded in the Austro-Hungarian Empire (later Czechoslovakia) this pioneer maker built four-stroke single cylinder and V-twin powered motorcycles using Zeus or Fafnir engines.

After WWII Achilles was re-established in Germany and began building Sachs two-stroke engine powered machines, which looked half scooter half motorcycle with 10in wheels and a floorboard. The launch model 147cc Sport was soon followed by a 175cc version. Other models employed 98cc and 123cc Sachs engines. Later, 48cc moped-style models joined the range. After production ended Achilles sold all motorcycle manufacture tooling and machinery to Norman of Ashford, Kent, UK.

Acme 1902-21 UK
Built by the Coventry Acme Motor Company, the Acme was given the advertising slogan of ‘the machine of no regrets.’ Solid, rather than exciting, single cylinder and V-twin models powered by proprietary engines including JAP and Minerva. Neighbours Rex took over Acme in 1919, first using the name Rex Acme in 1921. Very rare.

Adler 1902-07 and 1949-58 Germany
Established cycle makers who built a number of primitive De Dion powered clip on type machines and then motorcycles with their own engines. Production ended in 1907 in favour of bicycles, cars and typewriters, but Adler re-entered the motorcycle market in 1949 with the M100 designed by managing director and chief engineer Hermann Friedrich.

The 98cc commuter was comfortable, well made and enjoyed steady sales, prompting Adler to add three more models to the range for 1951 – two single cylinder two-strokes, the M125 and M150, and, significantly, their first twin the M200. The heart of which was a 195cc (48mm x 54mm) piston port two-stroke twin which led a year later to Adler’s best ever selling model, the MB250.

Powered by a responsive 247cc two-stroke twin with the square dimensions of 54 x 54mm, the MB250 ultimately had a worldwide impact. Both Suzuki (Colleda) and Yamaha (YD1) used the Adler MB250 and the sports version MB250S as role models for their world beating two-stroke twins. British designer Val Page gave the Adler more than a passing glance when he designed the Ariel Leader/Arrow engine.

Adler twins displayed a turbine-like smoothness through their rev range, which later became the hallmark of Yamaha and Suzuki, a usable top speed of over 75mph, comfort and a high build quality.

The company successfully entered a team of twins in the 27th ISDT held in Austria returning home with three golds and a bronze, but it was on the European road race circuits the Adler made its mark. All the more surprising as the company never supported a full works team and the racers were powered by modified road going engines.

Home tuned MB250s ridden by the likes of Hubert Luttenberger, Walter Vogel and Hans Hallmeier, began to clean up the places at many 1953 European 250cc races, prompting Adler to build ‘over the counter’ racers, the RS250 (Renn Sport) for the 1954 season. With frame design by Jan Drkosch and road going engines tuned by former aero engineer Kurt Grasmann, the 24hp RS250 accelerated rapidly and would hit almost 120mph. Private tuners grafted water-cooled barrels onto the model, some eventually extracting 38bhp and 140mph from the motors. Richard Williats raced an Adler with success on the British short circuits during the early Sixties.

For once, privateers could buy a 250cc racer at modest cost that could give rival works Grand Prix machines a run for their money. Sadly, sales of road going models slipped and despite the launch of a scooter, the 98cc three-speed, fan-cooled, two-stroke Junior in 1955, Adlers ended motorcycle production during the winter of 1957/58. After which Deiter Falk went on to give the marque its best ever racing season in 1958, fifth in the World Championship amongst a field of works machines.

Post-WWII Adlers survive in moderate numbers in mainland Europe, with a number of examples alive and well in Britain. The spares situation is mediocre, but if you like two-stroke twins try an Adler. The racing RS250 is rare and sought after.