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 having rigid edges and flexible angles has enough ‘diagonal’ struts to make it rigid, the smallest number of struts required is
If an arrangement of E rigid rods with flexible angles meeting in V vertices is ‘just rigid’, then 2V– E =
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.
 

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