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The Norton Manx or Manx Norton is a British racing motorcycle that was made from 1947 to 1962 by Norton Motors Ltd. A Norton had contested every Isle of Man TT race from the inaugural 1907 event through into the 1970s, a feat unrivalled by any other manufacturer, and the development and honing of the Manx racing motorcycle was another step in this racing achievement. New Manx Nortons, built to various specifications are still available to buy new, from various suppliers around the world. These suit different categories and definitions of Classic Motorcycle Racing and Historic Motorcycle Racing in different countries around the world. Norton's first use of the name 'Manx' was applied to the 'Manx Grand Prix' model available from 1936-1940, a special racing version of their 'International' roadster, with telescopic forks and a plunger rear suspension, magnesium for the crankcases and cambox, and no provision for lighting. Just after WW2, the 'Grand Prix' was dropped, and Norton named their 1947 racing model the 'Manx'. It was a lightly redesigned prewar racing Norton International, an overhead cam single-cylinder machine available as a 350cc or 500cc. The Norton factory race bikes under team manager Joe Craig were experimental models, and a version was available to buy from the factory in Bracebridge Street - to selected customers. Fitted with the McCandless brothers Featherbed frame for 1950, the Manx gained a new lease of racing life as a racing machine, the new frame giving the fine steering necessary for high speed navigation of some very fast racing circuits of the time. The last Bracebridge Street (the original home of Norton) Manx Nortons were sold in 1963. Even though Norton had pulled out of International Grand Prix racing in 1954, the Manx had become the backbone of privateer racing.〔 The Classic Motorcycle Racing movement from the 1970s onwards has seen relatively large numbers of Manxs return to the track, and a flourishing supply of parts and services has appeared all around the world to nourish this demand. == Development == The Norton Manx was developed to win the Isle of Man TT from single overhead cam international racers by Norton racing team engineer Joe Craig. The double overhead cam configuration was developed in 1937 and after many problems perfected one year later. The ''Manx'' was delayed by the outbreak of World War II but reemerged for the 1946 Manx Grand Prix. The motorcycle was upgraded with new telescopic forks and in 1948 gained twin leading shoe brakes. In 1950 the innovative Featherbed frame was developed, giving the Manx a significant competitive advantage through a low centre of gravity and short wheelbase that was perfectly suited the challenging island TT course. The all-welded, tubular featherbed frame was light and trim, without the usual forgings that added unnecessary weight. In 1950, the featherbed Manx recorded a double hat-trick of podium positions at the TT.〔(【引用サイトリンク】title=1957 Norton 30M )〕 The Manx engine was redesigned in 1953 with a much shorter stroke of to improve the rev range.〔 The major 1954 upgrade to the Manx was to have been an engine with the cylinder mounted horizontally to give a much lower centre of gravity – along the lines of the Moto Guzzi and Benelli racers. However, a decline in sales in the mid 1950s prompted a number of manufacturers to withdraw from GP racing in 1954, and Nortons did likewise. The Norton F Type Manx, as it was to have been, still exists, and restored is displayed in the Sammy Millers Museum Collection. With Nortons withdrawal from racing, Joe Craig retired after more than 25 years of coaxing ever more power and reliability from his single cylinder ''Cammy'' racers. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Norton Manx」の詳細全文を読む スポンサード リンク
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