50cc

The 50 cc class was the ultra-lightweight class in Grand Prix motorcycle racing, and formed part of the World Championships from 1962 until 1983; when the class was replaced by 80 cc.

The relative low cost and increasing availability of 50 cc motorcycles in the post-war period, spawned a number of club road racing events for this size of machine in the early 1950s. With the earliest events being held in Italy and in the UK. The potential of this class for providing entertaining but affordable racing was soon recognised with several national championships and in 1961 the FIM introduced The Coupe d' Europe, a series of international events for 50 cc machines, each with a minimum duration and run to established Grand Prix rules and regulations. The series attracted a variety of entries, but the dominating force were the work’s Kreidler team bikes. Based on a standard Kreidler Florett road bike, their single cylinder Kreidler Renn-Florett’s featured lightweight frames, a special cylinder head and barrel, twin 16 mm Bing carburettors feeding the engine through rotary valves and improved suspension and brakes. By the end of the season, with the addition of rudimentary streamlining and the increase of carburettor size to 17 mm, the 9 hp (6.7 kW) four-speed two-stroke bikes could top over 85 mph.

In 1962, the FIM followed up the success of the Coupe d’ Europe by giving the 50 cc class World Championship status. As well as the works entries of existing European manufacturers like Kreidler and Tomos, this development also attracted entries from Japanese manufacturers with both Honda and Suzuki entering full work’s teams. The Spanish Derbi factory also entered a single work’s bike for the Spanish Grand Prix.

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