We do know, here is the paper that the journalist refers to: http://www.sciencemag.org/content/332/6027/339 http://www.sciencemag.org/content/332/6027/339 And

We do know, here is the paper that the journalist refers to: http://www.sciencemag.org/content/332/6027/339 http://www.sciencemag.org/content/332/6027/339 And here is a great video by the author: http://www.youtube.com/watch?v=YdtE3aIUhbU http://www.youtube.com/watch?v=YdtE3aIUhbU Short answer: "a bicycle should turn into a fall."