T.C.F. Revue Mensuelle - October 1900
La Bicyclette à plusieurs développements

T.C.F. Revue Mensuelle October 1900 - La Bicyclette a plusieurs developpements scan 1 main image

Georges Delbruck argues that, just as motorcars need gears, so do cyclists. He suggests a startling six speed range with développements of:

  • 9.50m (119 gear inches) for speed in very favourable circumstances.
  • 7.50m (94 gear inches) for a good road on the flat.
  • 5.50m (69 gear inches) for undulating countryside.
  • 3.75m (47 gear inches) for hilly terrain.
  • 2.20m (28 gear inches) for mountain passes.
  • 1.10m (14 gear inches) for mountain trails.

Those 14 gear inches are no mean low gear! You would need a chainwheel of 18T driving a freewheel cog of 34T to give a ratio like that.

(Source gallica.bnf.fr/ Bibliothèque nationale de France)