Hub gear

Automotive transmissions
Manual
Automatic / Semi-automatic
Sturmey-Archer S3X

A hub gear,[1] internal-gear hub,[2] internally geared hub[3] or just gear hub[4] is a gear ratio changing system commonly used on bicycles that is implemented with planetary or epicyclic gears. The gears and lubricants are sealed within the shell of the hub gear, in contrast with derailleur gears where the gears and mechanism are exposed to the elements. Changing the gear ratio was traditionally accomplished by a shift lever connected to the hub with a Bowden cable, and twist-grip style shifters have become common.

Hub gear systems generally have a long and largely maintenance-free life though some are not suitable for high-stress use in competitions or hilly, off-road conditions. Many commuter or urban cycles such as European city bikes are now commonly fitted with 7-speed gear-hubs and 8-speed systems are becoming increasingly available. Older or less costly utility bicycles often use 3-speed gear-hubs, such as in bicycle sharing systems. Many folding bicycles use 3-speed gear-hubs. Modern developments with up to 18 gear ratios are available.

  1. ^ Oxford English Dictionary (2nd ed.). 1989. derailleur, n. 1950 Chambers's Encycl. II. 307/2 The most popular variable gear in Great Britain is the 3- and 4-speed hub gear... 1959 Elizabethan Apr. 35/1 My lightweight bike with 4-speed hub gear...
  2. ^ Cite error: The named reference brown was invoked but never defined (see the help page).
  3. ^ Bikes, Montague (May 26, 2011). "Why Use an Internal Gear Hub?".
  4. ^ "The Internal Gear Hub Review". Hubstripping.wordpress.com. Archived from the original on 2011-11-12. Retrieved 2011-11-21. Now you should be able to choose the gear hub group which fits your personal cycling purpose best!