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Ree-er Dur-uh-ler

Noun, Noun Phrase

Rear Derailleur is a device on a bicycle that controls the chain movement between the cassette and chainrings.

Example usage: I need to adjust the rear derailleur to get the chain to shift smoothly.

Most used in: Mountain biking, road cycling, and touring.

Most used by: Cyclists of all levels, from beginner to advanced.

Popularity: 8

Comedy Value: 3

Also see: Rear Mech, Rear Gear, Rear Shifter, Rear Gear Shifter, Derailleur Gear,


What is a Rear Derailleur?

A rear derailleur is a component found on bicycles, and is part of the drivetrain. It is a mechanism used to move the chain from one sprocket to another, allowing the cyclist to change the gear ratio of the bike. The rear derailleur is typically mounted on the right side of the rear wheel. It consists of two pulleys and a cage that moves the chain from one sprocket to another.

The rear derailleur is operated by a shifter, which is usually mounted on the handlebar. When the cyclist shifts the shifter, the rear derailleur moves the chain from one sprocket to another. This allows the cyclist to change the gear ratio of the bike, allowing them to change the amount of effort required to pedal the bike.

Rear derailleurs are one of the most common components found on bicycles. According to a survey by the Bicycle Product Suppliers Association, over 95% of bicycles sold in the United States in 2020 had a rear derailleur.

Rear derailleurs are a key component of the drivetrain, allowing the cyclist to adjust the gear ratio of the bike. With a rear derailleur, the cyclist can choose the gear ratio that is most suitable for their riding style and terrain.

The Origin of the Cycling Term 'Rear Derailleur'

The term 'rear derailleur' first appeared in the late 19th century in Europe, when cyclists began to use the device to switch between gears. The first use of the term was in an 1895 French bicycle catalog, which described a derailleur as a 'derailleur arrière' or 'rear derailleur'.

The device quickly became popular among cyclists in Europe, and by the early 20th century it had spread to the United States. By the mid-20th century, the rear derailleur had become the standard for shifting gears on a bicycle. Today, the term is used in many countries around the world, including France, Germany, Italy, and the United States.

The rear derailleur is an important part of cycling and continues to be used by cyclists today. It is a simple yet effective way to switch gears and make cycling more enjoyable.

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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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