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bot-əm brack-ət spɪn-əl

bottom-bracket, spindle

The spindle of the bottom bracket of a bicycle.

Example usage: I need to replace the bottom-bracket-spindle on my bike.

Most used in: Mountain biking circles.

Most used by: Cyclists who enjoy technical trails.

Popularity: 8/10

Comedy Value: 3/10

Also see: Crank Axle, Spindle, Bottom Bracket Shaft, Bottom Bracket Spindle,

Understanding the Bottom-Bracket-Spindle in Cycling

The bottom-bracket-spindle is a key component of a bicycle’s frame. It is a cylindrical axle that connects the crankset to the frame and allows the crankset to rotate. The spindle is usually made of steel, aluminum or titanium and is housed in the bottom bracket shell, which is the part of the frame that the crankset attaches to.

The length of the bottom-bracket-spindle is determined by the frame size and type of crankset. A standard spindle length is around 120 millimeters, but different sizes are available for different types of bikes. For example, a mountain bike with a triple crankset typically has a longer spindle than a road bike with a double crankset.

The bottom-bracket-spindle is an important part of a bike’s performance, as it determines the distance between the pedals and the frame, the amount of power transfer, and the efficiency of the bike. It is estimated that a properly sized spindle can improve a cyclist’s power output by up to 5%, and a poorly sized spindle can reduce power output by up to 10%.

When selecting a bottom-bracket-spindle, it is important to consider the size of the frame, the type of crankset, and the type of riding the bike will be used for. By understanding the importance of the spindle and selecting the correct size, cyclists can ensure their bike is performing at its best.


The Origin of the Term 'Bottom-Bracket-Spindle' in Cycling

The term 'bottom-bracket-spindle' first appeared in the cycling world in the late 19th century. It is believed to have originated in the United Kingdom, where the first bicycles were being developed. The term was used to describe the spindle that connected the crank arms to the frame of the bicycle.

The bottom-bracket-spindle was an important part of the bicycle as it allowed the pedals to move in a circular motion and transfer power from the rider to the wheels. The bottom-bracket-spindle was also used to hold the bearings that allowed the crank arms to rotate freely. This allowed the rider to pedal more efficiently and with less effort.

Today, the term bottom-bracket-spindle is used to refer to the same part of a bicycle, and is still an essential part of any cyclist’s setup. It continues to be used to describe the spindle that connects the crank arms to the frame of the bicycle and holds the bearings that allow the crank arms to rotate freely.

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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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