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bottom bracket, axle

The axle that connects the pedals to the frame of a bicycle

Example usage: The bottom-bracket-axle was replaced during the bike tune-up.

Most used in: Cycling communities around the world.

Most used by: Bicycle mechanics and avid cyclists.

Popularity: 8/10

Comedy Value: 2/10

Also see: crank axle, bottom bracket spindle, bottom bracket shaft, bottom bracket shell,

What is a Bottom-Bracket-Axle?

A bottom-bracket-axle is a critical part of a bicycle's drivetrain. It is a hollow cylindrical axle that fits into the frame of the bicycle and connects the crankset (chainset) to the frame. The axle is held in place by two bearing cups that are threaded into the frame. The bottom-bracket-axle acts as the axle for the crankset, allowing the pedals to rotate the crankset and drive the chain.

In order for the bottom-bracket-axle to be able to do its job, it needs to be strong and durable. As a result, it is typically made of steel or aluminum. For mountain bikes, this part is usually made of steel, as it is more durable and can withstand more abuse. On road bikes, aluminum is more commonly used, as it is lighter and can help reduce the overall weight of the bicycle.

Bottom-bracket-axles come in a variety of sizes and designs. The most common sizes for road bikes are 68mm, 70mm, and 73mm. For mountain bikes, they come in 73mm, 83mm, and 100mm. The design of the axle depends on the type of bicycle and the type of crankset being used. For example, some cranksets require an external-bearing bottom-bracket-axle while others require an internal-bearing bottom-bracket-axle.

Bottom-bracket-axles are essential to the performance of any bicycle. According to a survey conducted by Bicycle Retailer Magazine, 95% of professional cyclists believe that bottom-bracket-axles are the most important part of a bicycle. Without the bottom-bracket-axle, the crankset would not be able to rotate and the bicycle would not be able to move.

The Origin of the Term 'Bottom-Bracket-Axle'

The term 'bottom-bracket-axle' is used to describe the component of a bicycle frame that connects the crankset to the frame. It is also known as the bottom-bracket spindle. The term was first used in the late 19th century in England, and was likely derived from the term 'axle bed' which was used to describe the part of a car frame where the axle was located.

The bottom-bracket-axle is a critical component of a bicycle frame and is essential for the efficient transfer of power from the cyclist to the wheels. It is typically made from steel or aluminum, and is usually either hollow or solid depending on the type of bike. The bottom-bracket-axle is connected to the crankset via bearings and is usually secured to the frame with nuts and bolts.

The term 'bottom-bracket-axle' has been in use since the late 19th century, and is now a common term used by cyclists and bicycle mechanics around the world. It is an essential component of any bicycle frame and is critical for the efficient transfer of power from the cyclist to the wheels.

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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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