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Tour De France: Simon Smart talks hi-tech cycling

16 July 2013 Last updated at 09:17 BST

The teams behind the world's fastest cyclists are obsessed with the small details that, when added up, separate the champions from the also-rans.

Simon Smart, founder of Smart Aero Technology, is renowned for his ultra-fast bikes, painstakingly tweaked for maximum performance.

The process is a complicated and sophisticated one, as he demonstrated to the BBC at the Smart Aero headquarters in Brackley, England.

Read More: The technology behind the Tour

Video journalist: Dave Lee