Ignoring the front forks, the frame of a bicycle is essentially a quadrilateral with a diagonal strut. This is because the resulting triangles are rigid. If an n-sided polygon with rigid edges and flexible angles has enough ‘diagonal’ struts to make it rigid, the smallest number of struts required is






The world record speed for bicycle riding in 2001 was held by Sam Whittingham, who rode over a distance of 200 metres at a speed of 129.6 kph. It represents the world’s fastest human propelled by his own power.
 

This answer is wrong.
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