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Related to derailleur: Derailleur gears


A device for shifting gears on a bicycle by moving the chain between sprocket wheels of different sizes.

[French dérailleur, from dérailler, to derail; see derail.]


(Mechanical Engineering) a mechanism for changing gear on bicycles, consisting of a device that lifts the driving chain from one sprocket wheel to another of different size
[French dérailleur derailer]


(dɪˈreɪ lər)

a gear-shifting mechanism on a bicycle that shifts the drive chain from one sprocket wheel to another.
[1945–50; < French dérailleur literally, a device causing disengagement or derailing]


[dəˈreɪljəʳ] n derailleur gears npl (Cycling) → deragliatore m
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References in periodicals archive ?
With an average grade of 18 percent and a steepest section of 24 percent, George Street is no place to use a derailleur.
Royal blue, with three derailleur gears operated by a lever on the handlebars.
For example the 20-speed Shimano XTR derailleur gearset is tried and tested by competitors worldwide while other features include Magura hydraulic disc-brakes and Crank Brothers wheels with low-rolling resistance tyres.
KEY FEATURES: Polygon Air suspension seatpost, Shimano Deore XT rear derailleur, LX shifters, bar ends and anti-puncture tires.
The bikes are equipped with a seven-speed derailleur and cruise control, as well as head and tail lights.
You'll find indexed shifters on a few new bikes (more in 1987), or you can retrofit your old bike with one (new rear derailleur, gears, levers, and chain) for around $90.
Seasonal and special occasion ales such as Bluebelly Barleywine and Derailleur biere-de-garde are also brewed.
A Shimano Nexus 8 speed internal hub eliminates a derailleur, providing a low maintenance solution and allows gear changes even when stopped.
The 7-speed Shimano Tourney gears and shifter work together with a TX-31 rear derailleur and gearbox, allowing the rider to pedal, to activate the Twist and Go (TAG) system which activates the motor when the throttle is turned, or the Power Assist (PA) mode, which can make pedaling easier as the engine comes on to provide a boost at every rotation of the pedals.
The Shimano TX 31 rear derailleur helps with quick shifts and the scram grip shift shifters-say that three limes fast--facilitate fast and easy gear changes.
CUTLINE: (1) Gray Harrison, right, one of the Earn-A-Bike shop managers, helps Will Colan, a student at Clark University with the derailleur on his bike.