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The Velocette Thruxton was a sporting motorcycle produced by Velocette between 1965 and 1971. Revealed at the 1964 Earls Court Show, it was the final development of Velocette's antiquated pushrod single, the Venom.〔''Motor Cycle'', 19 November 1964. 'Earls Court Show Guide'. p.861/2. "''High spot of the latest Velocette presentation is the Venom Thruxton 500—one of the Venom family, obviously, but trimmed for racing.''" Accessed 2013-08-17〕 Sometimes referred to as the ''Venom Thruxton'' or simply ''Thruxton'', some surviving examples could be 'upgraded' replicas based on the Venom or Viper, as many parts in the range were interchangeable. Due to the high values involved and possibility of fakes, a register was established by a member of the Velocette Owners Club, using production data of engine and frame numbers acquired after the factory closure, to enable owners and potential buyers to confirm provenance when selling and buying.〔''The Classic Motor Cycle'' July 1996, p.39 ''Register that Thruxton'' Accessed and added 2014-06-27〕 The Thruxton ceased production only when the company folded in 1971. ==Development== An optional cylinder head for the Venom became available for racers in 1964;〔''Motor Cycle'' 15 October 1964 pp.698-699 Velocette 1965 Range. ''Super-Speed Venom. "Scintillating news from Velocettes about the 1965 range is not of a machine as such. It concerns a catalogued extra for thew 499 cc Venom Clubman—an ultra-high-performance cylinder head which, in conjunction with a 13/8"-choke Amal GP carburettor, is claimed to give the Venom a potential of around 135 mph! Intended for racing, the new cylinder head is an individually made tool-room job rather than a production item...When the cost of the head and carburettor, plus specially modified fuel and oil tanks, is totalled, the extras bill comes to around £64.''". Accessed 2015-04-22〕〔(MSS to Thruxton, by ''Rod Burris'' ) at Google books Retrieved 2015-04-22〕 a Venom equipped with this revised cylinder head took first in its class at that year's ''Thruxton 500'', a endurance road race. Veloce introduced the Venom Thruxton production model in 1965 with an advertised 41 horsepower at the crankshaft. Period tests clocked it at without race tuning. The well-proven Venom was improved by Velocette designer (and owning-family member) Bertie Goodman with rearward placed footrests having brake pedal and remote gear-change linkage to suit, close-ratio four speed gearbox, alloy rims, twin-leading shoe front brake and 'clip-on' handle bars. The engine gained a race specification cylinder head to accommodate extra-large valves, a downdraught inlet port and an Amal 5GP2 13/8 bore carburettor〔 with extended inlet tract which was so long it required a special cut out in the rear of the fuel tank. The upgraded engine delivered , 5 bhp more than the Venom.〔 It was important for eligibility in endurance races such as the Thruxton 500 that competing motorcycles were genuine production machines, but although the Velocette Thruxton was sold in a road-going version, it was really targeted at the racing fraternity. No more than 1,108 Thruxtons were manufactured before the company collapsed in 1971.〔(【引用サイトリンク】title=Velocette 1965 Thruxton 500cc )〕 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「Velocette Thruxton」の詳細全文を読む スポンサード リンク
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