Parts in a bicycle drivetrain include:

  • Pedals
  • Crankset
  • Bottom-bracket
  • Chain
  • Cassette
  • Freehub

Motive power in a bicycle flows as follows:

  1. Pedals
  2. Crankset
  3. Bottom-bracket
  4. Chain
  5. Cassette
  6. Freehub