How to choose your road bike bottom bracket?
Ensuring the best possible rolling smoothness for your crankset, this component must conform to the standard of the frame as well as the crankset. Between frame standards and crankset standards, a little help is most welcome!
The standards
- The bearing type: steel or ceramic
- The crankset axle type: Hollowtech II, GXP, BB30, etc.
- The bottom bracket type on the frame: BSC, BB30, etc.
Types of bottom brackets
Let's start with the simplest aspect: bearing quality. You will generally find the same bottom bracket available with steel or ceramic bearings. The ceramic used for bicycle bearings has a harder and unalterable surface compared to steel. The advantages are therefore a low friction coefficient and an increased lifespan without the need for maintenance. However, please note that this is only valid for 100% ceramic bearings, meaning both the balls and the races.
For compatibility with the crankset axle, things start to get complicated. Depending on the brand, there are different standards. To help you identify what you need, here is a list of the most common ones:
- Hollowtech II, Megaexo: 24 mm diameter axle
- GXP: 22 mm diameter axle on the left, 24 mm on the right
- Power-Torque: 1-piece axle with 25 mm diameter
- Ultra-torque: 2-piece axle with 25 mm diameter
- BB30: 30 mm diameter axle
As if the bottom bracket axle standard were not enough, the shell must also match the frame standard. Here is further guidance for the most common ones:
- BSC (also known as BSA): the internal diameter of the frame is 34.8 mm
- Press-Fit: the internal diameter of the frame is 41 mm
- Press-Fit30: the internal diameter of the frame is 46 mm
- BB30: the internal diameter of the frame is 42 mm
Please note, some road frames have an extended bottom bracket shell for a specific crankset, such as the 386EVO system which is an extended BB30.
Which bottom bracket should you choose for your riding style?
In the case of a bottom bracket replacement, you will not necessarily have a choice beyond bearing quality. Indeed, the choice will be determined by your frame standard and your crankset axle.
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ROAD - Bottom Brackets and Bearings
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FSA PRESSFIT BB86 MEGAEXO Bottom Bracket 24mm Axle 86.5mm
Regular price 18,89 €Regular priceUnit price per -
SHIMANO SM-BBR60 ULTEGRA / 105 BSC Bottom Bracket
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SHIMANO BB-RS501 BSC Bottom Bracket
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SHIMANO SM-BB9241 DURA-ACE Press Fit 86.5 mm Bottom Bracket
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ROTOR PRESS FIT 41-30 Bottom Bracket
Regular price 51,44 €Regular priceUnit price per -
STRONGLIGHT JP400 BSC crankset Alu cups
Regular price From 29,93 €Regular priceUnit price per -
SHIMANO SM-BB7141 Press Fit 86.5 mm Bottom Bracket
Regular price 26,24 €Regular priceUnit price per -
STRONGLIGHT JP400 Italian crankset Alu cups
Regular price 30,44 €Regular priceUnit price per
