Compare prices on:ShiftersShifters |A bicycle shifter, also known as a gear control or gear lever, is a component used to control the gearing mechanisms and to select the desired gear ratio. Typically, they operate either a derailleur mechanism or an internal hub gear mechanism. In either case, the control is operated by moving a cable that connects the shifter to the gear mechanism. Shifters are mounted on the down tube of the frame, on the handlebars, or at the ends of triathlon bars. Major manufacturers of shifters include Shimano, Campagnolo, and SRAM.|
The controls are mounted so that the right shifter controls the rear derailleur and the left shifter controls the front derailleur. For hub gears, the control is also mounted on the right.
The trend in shifting development has been to reduce the need for the rider to direct attention away from riding. Friction shifters gave way to index shifters, which do not require fine-tuning during a gear change.
Originally, gear levers consisted of a simple lever. Changing gears required pushing or pulling the lever so that the dérailleur would move the chain to a different sprocket
on the rear hub.
The cyclist would need to adjust the lever to center the chain on the sprocket.
These systems are still used on triathlon bikes now, where the rider will often sacrifice the benefits of index shifting to get the shifters in the right spot on their aero bars.
Index shifting is a system where the control has discrete stops. Hub
gears by design are indexed, so for derailleur systems, indexing was an innovation. Each stop corresponds to one position of the derailleur. This allows the cyclist to change gear without having to adjust each time, as in friction shifting.
Mountain Bike Shifting
shifters started out as friction shifters, but now they are primarily indexed, like road bikes.
Modern grip shifters are indexed as well and they have the added benefit of letting the rider shift the bike without having to release any fingers from the handlebars,
thereby remaining in more control over the bike's steering.