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Noun, Proper Noun

Derailleur is a device that moves the chain to different sprockets on a multi-gear bicycle.

Example usage: I need to adjust the derailleur to shift to the next gear.

Most used in: Mountain biking and road cycling.

Most used by: Experienced cyclists.

Popularity: 8/10

Comedy Value: 2/10

Also see: Shifter, Gear Mech, Gear System, Drivetrain,


The Definition of the Cycling Term Derailleur

Cycling is a sport that requires an understanding of many specialized terms and pieces of equipment. One of the most important pieces of equipment for cyclists is the derailleur. A derailleur is a mechanism used to shift gears on a bicycle, allowing the rider to change resistance levels and ride at different speeds.

Derailleurs come in two varieties – front derailleur and rear derailleur. The front derailleur works by moving the chain between two or three chainrings at the front of the bike. This allows the rider to switch between different gear ratios. The rear derailleur is responsible for moving the chain between the cogs on the rear cassette. This allows the rider to switch between different levels of resistance.

Derailleurs are an essential piece of equipment for cyclists, regardless of the type of riding they are doing. According to a survey conducted by the National Bicycle Dealers Association, over 90% of bicycles sold in the United States come with a derailleur.

It is important for cyclists to understand how to use and maintain their derailleur. Failure to properly maintain a derailleur can result in poor shifting performance and even damage to the bike. Taking the time to learn about the derailleur and how to use it properly can help ensure a safe and enjoyable cycling experience.


The Origin of the Cycling Term 'Derailleur'

The cycling term 'derailleur' is believed to have originated in the early 1900s, and is thought to have been a French word first used to describe the device which changed the chain's movement between sprockets on a bicycle.

The mechanical device was first patented by the French inventor Paul de Vivie in 1905, and was initially known as a 'dérailleur'. The device was designed to replace the manual manipulation of the chain, which was necessary to change the gear ratio of a bike.

The word 'derailleur' is thought to have been derived from two French words - 'dérailler' meaning 'to unrail' and 'raille' meaning 'rail'. This is reflective of how the device works, as it unrails the chain from the sprocket it is currently on, and moves it along the rail to the next sprocket.

The device and the term 'derailleur' quickly spread across the world, and by the 1930s the device was commonly used on most bicycles. The derailleur has evolved significantly since its inception, and is now available in several different forms, such as the indexed and electronic derailleurs.

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Saddle Slang

Find definitions for all of the technical terms, slang, and acronyms used in cycling. From the different types of bikes and their components, to training techniques, racing terminology and put downs, this dictionary has it all.

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