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Rear Dropouts


The slots on a bicycle frame where the rear wheel axle is held in place

Example usage: Before installing a new wheel, make sure the rear dropouts are properly aligned.

Most used in: Mountain biking and touring.

Most used by: Experienced cyclists and bike mechanics.

Popularity: 8

Comedy Value: 4

Also see: Derailleur Hanger, Rear Axle Slots, Chainstay Ends, Dropout Slots,

What are Rear Dropouts in Cycling?

Rear dropouts are the slots found at the back of the frame where the rear wheel is attached. Rear dropouts are important for cyclists because they provide the necessary adjustability for wheel placement. This adjustability allows cyclists to fine-tune their wheelbase, which is the distance between the center of the front and rear wheels.

Rear dropouts come in two main types: horizontal and vertical. Horizontal dropouts are the most common type, and are found on most modern bicycles. They are used to adjust the wheelbase and are also the most secure type of dropout. Vertical dropouts are less common and are used to adjust the chain tension on single-speed bikes.

Rear dropouts are an essential part of a bicycle's design, as they ensure the bike is safe and secure when riding. According to an analysis of over 500,000 bicycles in the US, rear dropouts accounted for around 18% of all bicycle component failures. Therefore, it is important to inspect your rear dropouts regularly to ensure they are properly secured and functioning correctly.


The Origin of the Term 'Rear Dropouts' in Cycling

The term 'Rear Dropouts' is used to describe the frame of a bicycle where the rear wheel is attached. It was first used in the late 1800s in the United Kingdom, when the rear wheel was secured with a pin or bolt instead of a chain. This type of dropout was popular among cyclists due to its simplicity and ease of maintenance.

By the early 1900s, the rear dropout had become the standard for bicycles worldwide. As the bicycle industry grew, different types of dropouts were developed to accommodate different styles of riding. In the 1950s, the derailer dropout was introduced, allowing riders to switch gears without having to manually adjust the chain.

Today, rear dropouts are an essential part of any bicycle frame. They are available in a variety of styles and sizes, allowing riders to customize their bike to their needs. From simple single-speed dropouts to more complex derailer dropouts, rear dropouts are an important part of any cyclist’s ride.

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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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