Another sensation in 1919 was the ABC motorcycle. The famous designer Granville Bradshaw designed it back in 1913, but it was only in 1919 that it finally began to be produced by the well-known aviation company Sopwich. Interestingly, soon under license began its production in France, another company that came down from heaven - known for its aircraft engines "Gnome Rhone". The two-cylinder opposed motorcycle engine had overhead valves, a four-speed gearbox, a duplex frame and suspension of both wheels on quarter-elliptic springs. The engine was located according to a familiar scheme: the crankshaft is longitudinally in relation to the direction of movement of the motorcycle. The only thing missing was a little bit: the drive on the rear wheel was a chain, not a shaft. But in general, the impact of this motorcycle on the BMW, which appeared a few years later, is obvious.
The Stevens brothers began production of motorcycle engines in 1906, and in 1909 released their first motorcycle, called AGS - on the initials of one of the brothers, Albert John Stevens. During the First World War, the company produced military equipment, and after its completion resumed production of its models with lower-valve engines - single-cylinder 550-cubic and 800-cubic with a two-cylinder V-shaped engine - one of the best among the bikes designed for use with a stroller. The Stevens brothers themselves were avid motorcyclists, and soon after the war they created a special racing motorcycle with an overhead valve engine, with valves in the cylinder head under the letter "V", forming a hemispherical combustion chamber. Named the "Big Port" (Big Hole), it won four consecutive Trophy Tourist races in 1920.1921 (two classes) and 1922. By the middle of the twenties, the overhead valve engines were widely used on road bikes, and this racing model became the basis for the company's most popular road car. In 1927, another successful racing car of the company appeared - with the upper camshaft driven by a chain.
Ariel" company in the early twenties produced motorcycles with single-cylinder and twin-cylinder engines of various engine manufacturers, but could not achieve success with customers. The changes began when Jack Sangster, the son of the founder of the company, came to power. He lured a talented designer Val Page from JAP, who by 1926 had developed a 550cc single-cylinder engine in two versions - a lower-valve and upper-valve. The new model immediately won the favor of the public.
William Braf has been producing motorcycles, which in general did not differ from the usual level, since 1902. His son George had his own views on what the bike should be, and in 1919 he founded his own company, calling it "Braf-Superior", that is, "Excellent". If in the twenties it was believed that the high-speed single motorcycle is much better suited to the overhead single-cylinder engine, George Brafe bet on large V-shaped "twos". Glory came to him in 1924, when he introduced the famous "Braf-Superior SS 100" with a two-cylinder overhead valve engine. The number "100" meant that the motorcycle had a guaranteed speed of 100 miles per hour - that is, 160 km/h. Of course, the company's motorcycles were very expensive and produced in small quantities, but for their dynamics and excellent quality they enjoyed a very high reputation.
BSA bikes were also famous for their quality, although unlike the elite Braf-Superior, they were among the most common motorcycles. In the production program in the twenties were light 175cc motorcycles with two-stroke engines, as well as motorcycles with four-stroke single-cylinder and two-cylinder V-engines with a working volume from 250 to 1000 cm3. And the quality was inherited: before starting production of motorcycles in 1909, the company for many years was engaged in the production of weapons (the name of the company is deciphered as "Birmingham small arms").
English company "Veloce" produced under the brand name "Velocet" light motorcycles with two-stroke and four-stroke engines. In 1926, the famous model "K" with the upper camshaft, which received a drive through a vertical shaft and bevel gears, appeared. In the same year, Alec Bennett won the 350 cm3 Trophy Tourist race in the racing version of this model. In 1928, an improved version of this model was released, called "KTT" (the letters "TT" were to remind of the victory in the "Tourist Trophy"). This motorcycle was the first to have a modern, foot-operated gearshift mechanism. It also became the winner of the Trophy Tourist twice - in 1928 and 1929.
Continued in the next part...
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