What to Consider
Plenty of factors can make finding a bottom bracket a confusing endeavor. Here’s what you need to know when shopping for bottom brackets.
Know Your Crankset and Frame Type
Your bottom bracket (BB) is an unseen component that connects your crank to your bicycle frame, providing the ability to power the drivetrain. It’s inserted into your bicycle frame’s bottom bracket shell, and typically includes bearings that help your crank’s spindle rotate. Because every frame and crankset is different, replacing a BB requires some research to determine if a particular bottom bracket is right for your bicycle.
It’s important to know your bottom bracket shell and spindle widths when purchasing a new BB. If you’re unsure if a bottom bracket will fit, refer to your manufacturer's website as a resource—most list which BBs are compatible with your frame. Bottom brackets will also sometimes come packaged with spacers to help get an exact fit, while adapters can also help.
You should also be mindful that some manufacturers require brand-specific tools in order to install a bottom bracket yourself, so if you plan on doing your own maintenance, ensure you have all of the necessary components. You may have to order a special tool from a manufacturer’s website for installation.
Threading
Threaded bottom brackets are the most common for modern bikes. These are bottom brackets where threads are cut into the frame’s bottom bracket shell, and bearing cups are then threaded into the shell. BSA/English bottom brackets, which have counterclockwise threading, are most often seen today. The less-common Italian threading, which is threaded clockwise, can also be purchased, however. Threaded BBs have the widest range of compatibility with cranksets.
Press-fit bottom brackets are directly placed into a frame’s bottom bracket shell and are often made with more affordable parts. These usually require special tools to be installed. Press-fit BBs have a reputation for making creaky noises over a shorter amount of time than threaded models, but that may not always be the case. It should also be noted that modern threaded bottom brackets, while advertised as such, are often bearings that have been press-fit into cups.
How We Evaluated
We researched and consulted several lists from professional critics, in addition to various Reddit and message board threads, for the most recommended and top-rated bottom brackets that money can buy. We then took a look through hundreds of user reviews from retailers like Amazon and Backcountry and compared ratings, read through complaints, and studied what makes a solid bottom bracket. The results of this list are a combination of the most raving user and professional reviews, and the top user ratings across retailers.