Bicycle gears

thumb|Shimano 600 front derailleur (1980)

thumb|A Shimano 105 crankset with two chainrings on a road bicycle right|thumb|A Shimano Deore right crankset, showing crank arm, spider, three chainrings and chainring guard thumb|right|Belt-driven bicycle|Belt-drive crankset on a Trek District

thumb|10-speed bicycle cassette

aspect of a bicycle drivetrain that determines the relation between the cadence, the rate at which the rider pedals, and the rate at which the drive wheel turns

indication of the mechanical advantage of different gears