
A
bicycle
A bicycle, also called a pedal cycle, bike, push-bike or cycle, is a human-powered transport, human-powered or motorized bicycle, motor-assisted, bicycle pedal, pedal-driven, single-track vehicle, with two bicycle wheel, wheels attached to a ...
shifter or gear control or gear levers is a component used to control the
gearing mechanisms and select the desired
gear ratio
A gear train or gear set is a machine element of a mechanical system formed by mounting two or more gears on a frame such that the teeth of the gears engage.
Gear teeth are designed to ensure the Pitch circle diameter (gears), pitch circles of e ...
. Typically, they operate either a
derailleur
Shimano 600 front derailleur (1980)
A derailleur () is a variable-ratio bicycle gearing system consisting of a chain, multiple sprockets of different sizes, and a mechanism to move the chain from one sprocket to another.
Modern front and rea ...
mechanism or an internal
hub gear
A hub gear, internal-gear hub, internally geared hub or just gear hub 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 h ...
mechanism. In either case, the control is operated by moving a
cable
Cable may refer to:
Mechanical
* Nautical cable, an assembly of three or more ropes woven against the weave of the ropes, rendering it virtually waterproof
* Wire rope, a type of rope that consists of several strands of metal wire laid into a hel ...
that connects the shifter to the gear mechanism.
Location

Traditionally shifters were mounted on the
down tube
A bicycle frame is the main component of a bicycle, onto which wheels and other components are fitted. The modern and most common frame design for an upright bicycle is based on the safety bicycle, and consists of two triangles: a main triangle ...
of the frame or
stem
Stem or STEM most commonly refers to:
* Plant stem, a structural axis of a vascular plant
* Stem group
* Science, technology, engineering, and mathematics
Stem or STEM can also refer to:
Language and writing
* Word stem, part of a word respon ...
. For ergonomic reasons, they tend to be located somewhere on the
handlebars on modern bicycles.
Mechanisms

There are various types of shifter:
* Grip shifter - a wheel with click stops surrounding the handlebar is turned until the desired gear is reached, though typically one gear at a time
* Trigger shifter - a lever is pulled or pushed to change gears one at a time
* Thumb shifter
* Road bike shifter - integrated with brake levers, sometimes known as a "brifter".
In 1990, Shimano introduced their
Shimano Total Integration
Shimano Total Integration (STI) is a gearshift system designed by Shimano for racing bicycles. It combines the braking and gear shifting controls into the same component. This allows shifting gears without having to remove a hand from the bars, u ...
, STI, shifting levers for road bicycles, this was an indexed shifting system and the first to integrate shifting with the brake levers. Campagnolo soon followed with their
ErgoPower system. The
SRAM Double Tap
SRAM Double Tap is an integrated Shifter (bicycle part), gearshift and Bicycle brake#Brake levers, brake lever system designed by SRAM Corporation for racing bicycles. It allows shifting gears without having to remove a hand from the bars, unlike p ...
was introduced in 2005.
See also
*
Electronic gear-shifting system
An electronic gear-shifting system is a method of changing gears on a bicycle, which enables riders to shift with electronic switches instead of using conventional shifter (bicycle part), control levers and mechanical cables. The switches are con ...
*
Outline of cycling
Cycling, also known as bicycling or biking, is the activity of riding bicycles or other Human-powered transport, human-powered vehicles with Wheel, wheels, for transportation, recreation, exercise, sport, and other purposes.
People who engage i ...
References
{{Commons category, Bicycle gear shift levers
Bicycle parts