The period between the end of the First World War and the beginning of the "Great Depression" - a colossal economic crisis that swept all capitalist countries in 1929 - was often referred to as the "golden era" in the history of the motorcycle. By that time, the bike had gained a reputation as a reliable vehicle, already available at a price of almost any worker with a decent salary. He had not yet faced competition from the car, except in the United States. Operating a motorcycle was also incredibly cheap: no fuel crises yet smelled. So it is not surprising that the bike became widespread - in Britain, for example, by 1929 there were more than 700 thousand motorcyclists.
The portrait of the "typical motorcycle" of 1918 will be much more rich in various colors than in 1901. First of all, by this time there were already three main motorcycle classes. The most widespread were motorcycles, as we would now put it, "medium cubic meters" - with single-cylinder four-stroke engines with a working volume from 300 to 500 cm3. The vast majority of these engines had both force-operated and lower-positioned valves; however, some engines had a lower outlet and upper inlet valve, a clear legacy of the time when the inlet valve was automatic. Carburetors - of the pulverization type - have long been forgotten about the primitive evaporative carburetors. Ignition is from high voltage magneto. In a separate unit there was a two- or three-speed gearbox. The drive on the rear wheel was a roller chain, although belt drive was also often found.
The tubular frame did not resemble a bicycle frame anymore. The front wheel was usually suspended in a parallelogram fork of the Druid type or in a lever system. Rear wheel suspensions remained rigid - very few companies, such as the German NSU, introduced spring elements between the frame and the triangle of the rear suspension. Some chain-driven motorcycles already had drum brakes with sliding blocks, but much more often the brake was a shoe brake in which the block pressed on top of the pulley - either a belt drive or a special rim on the front wheel.
The lighting was often from acetylene lanterns, although there were already electric lights. But they received energy from the battery, which had to be recharged while parking from the mains. Only on American motorcycles, which have always tried to resemble cars as much as possible, have already appeared generators of current - "Indian" even in 1916 tried to produce motorcycles with electric starter!
Heavy motorcycles - from 500 cm3 and above - usually had two-cylinder V-shaped four-stroke engines, lower-valve or with an upper inlet valve. English company "Douglas" since 1907 produced very popular motorcycles with two-cylinder opposition engine; however, the engine was located in the frame not as we are accustomed to our "opponents", and with a transverse crankshaft: one cylinder looked forward in the course of the machine, the second - back. Belgian FN and American Henderson had in-line four-cylinder engines.
Lightweight bikes - up to 300 cm3 - were often equipped with single-cylinder two-stroke engines, although the four-stroke ones still prevailed. Very often, they did not have a gearbox, and the drive, as at the beginning of the century, was a belt directly on the rear wheel.
The leading motorcycle power was, of course, the United Kingdom in those years. At motorcycle shows in 1919, more than a hundred companies presented their products! Many of them, of course, were simply engaged in the assembly of motorcycles from purchased on the side of knots and parts. So the motorcycle industry in Great Britain was formed not only by motorcycle companies, but also by a huge industry of aggregates, among which stood out engine companies "Villiers" and "JAP". "Since 1914, Villiers specialized exclusively in two-stroke engines, and JAP, which produced its first production engine in 1902, produced four-stroke engines. Power units of these two companies used not only British, but also numerous companies in continental Europe.
The first postwar years included the very first "scooter boom". Small cars with small diameter wheels (although there were scooters with "normal" size wheels), open frame and comfortable seat-chair suddenly became extremely popular - although this popularity was enough for only five years. The engine was either left in front, covered with a casing, or already placed under the seat, as on today's scooters. However, it was seldom possible to see the front shield and flat floor, which protect the driver from road dirt.
Continued in the next part...
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