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How can a bicycle coast without its pedals turning?

Stop pedaling and the bicycle can keep rolling. A freewheel mechanism lets the rear wheel turn without driving the pedals, then catches when you pedal again. Explore how that one-way connection works and why a small gap can appear before it engages.

3–5 min

Questions you could explore

  • What changes inside the hub between coasting and pedaling?
  • How do ratchets or pawls allow movement in one direction and transmit force in the other?
  • Why does engagement at the hub feel different at the pedals?

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How can a bicycle coast without its pedals turning? | Speech Topic | speaking.app