PBT BB Removal Tool LOW RES 970 x 600-2

BOTTOM BRACKETS: What they are, what they do and how to remove and replace them

If you’ve never heard of a bottom bracket, don’t worry, a lot of people haven’t!

This is our quick guide to caring for one of the most important parts of your bicycle – the bottom bracket.

What is a bottom bracket?

A bottom bracket (BB) is a component with a bearing that is buried inside your frame. It’s used to connect the cranks to the rest of the bicycle, and allows them to rotate freely. No BB means no pedalling, as the cranks would be stuck in place without it!

Think of it as like an axle in a car.

There are a number of types of bottom brackets used in modern bicycles, and they all fall into the category of either ‘Threaded’ or ‘Press Fit.’ This refers to how they are installed into the bicycle – either ‘pressed’ into the frame or threaded. When servicing or buying a replacement bottom bracket, you need to be sure you know which one is compatible with your bicycle.

Wear and tear

Like all moving parts of your bicycle, your bottom bracket needs a little TLC every now and then and will require occasional replacement.

As the BB contains a bearing, if you fail to keep it well-maintained it will stop rotating as efficiently and will feel stiff and gritty as you pedal. So when your bottom bracket is dying, you need to push harder just to turn the pedals. Not ideal!

How fast your bottom bracket wears down is dependent on how often you ride and where you do it. If you rarely ride and only cycle on clean, dry roads, your BB could last years! But if you’re riding through wet mucky trails every day, all that mess will start to work into your bottom bracket’s bearing and wear it down.

Lucky for you all, removing a BB in order to clean it up or replace it is a relatively straightforward task, and we’ve got the tools for the job!

How to remove a Threaded bottom bracket
  1. Remove the cranks – this will require a heavy-gauge Allen Key, typically sized 8mm. The PRO BIKE TOOL Allen Key Set includes one of these. Simply loosen the non-drive side bolt and pull the cranks out of the frame.
  2. Insert the PRO BIKE TOOL BB Tool into the left ‘cup’ of the bottom bracket – i.e., the side away from your drivetrain. Turn the tool counterclockwise to remove the cup.
  3. Repeat the process but turn clockwise to remove the right-side cup. The BB is now free and ready to remove!
How to remove a Press Fit bottom bracket
  1. Remove the cranks per step 1 above.
    Remove the dust caps that cover the bearing seals from either side of the bottom bracket.
  2. Use a Press Fit BB removal tool (watch this space for a PRO BIKE TOOL product to help you with this!) to remove the first bearing by inserting the head of the tool into the bottom bracket. Push the tool all the way through the bottom bracket until you have a secure fit against the bearing at the side farthest away from you. Push the guide stopper of the tool to sit flush against the near side of the bicycle.
  3. With the head of the BB tool firmly secure against the far-side bearing, use a hammer to tap the handle of the tool and dislodge the component. Do this firmly but carefully and the bearing will slowly creep out.
  4. Repeat the process to remove the bearing from the other side.

Once you have cleaned up your old bottom bracket with a rag and cleaning agent or have a new one to replace it, it’s time to install it!

How to install a Threaded bottom bracket
  1. Ensure the bottom bracket shell is nice and clean to start, and then rub grease into all the threads using a finger or brush.
  2. Figure out which BB cup goes on which side of the bearing. The non-drive-side has a left-hand thread and the drive-side cup has a right-hand thread.
  3. Grease the first cup, insert it into the relevant side of the bottom bracket and finger-tighten it. Once the bearing is as tight as you can get it by hand, use either the PRO BIKE TOOL BB Tool or a bottom bracket spanner to tighten it further.
  4. Repeat the above process with the other bracket cup.
  5. Reinstall the cranks.
How to install a Press Fit bottom bracket
  1. Ensure the bottom bracket shell is nice and clean to start.
  2. Use a bearing cup press (watch this space for a PRO BIKE TOOL product to help you with this!) to ‘push’ the first bearing into the frame. Put the bearing onto the shaft of the tool and insert the tool into the bottom bracket shell. Rotate the handle of the tool to firmly but carefully press the bearing into the BB shell. One the bearing is secure, slide the tool out of the bicycle.
  3. Repeat the process on the other side to install the second bearing. This will require a little more muscle as you are both installing the bearing and connecting the two sides of the component together by pushing them into each other.
  4. Reinstall the cranks.

If you thought "BOTTOM BRACKETS: What they are, what they do and how to remove and replace them" was a great read. Here are some related articles for you.

Like this PRO BIKE TOOL article about BOTTOM BRACKETS: What they are, what they do and how to remove and replace them! Why not Share it with your fellow cyclists!

Share on facebook
Share on Facebook
Share on twitter
Share on Twitter
Share on linkedin
Share on Linkedin
Share on pinterest
Share on Pinterest
BOTTLE CAGES
VIEW
CO2 INFLATORS
VIEW
TOOLS & MAINTENANCE
VIEW
BIKE PUMPS
VIEW

Best Apps for Bike Riders!

Looking to get fitter, explore new routes, or dial in your diet? There’s an App for all of those things, and more.

Here are the five best cycling Apps for Android and iPhone:

Read More

PRO BIKE TOOL Gift Guide 2020

The only thing a cyclist likes as much as a new bike is a new tool or accessory to play with.
But what to get your favourite cyclist for Christmas? There are a lot of gadgets you can get that rider in your life, and it can become a bit overwhelming. Luckily we’re here to help, and have created our 2020 gift guide!

Read More

FIVE TOP TIPS FOR WINTER CYCLING

Winter is nearly here, and it’s time to get ready for the chilly air and dirty roads of the off-season.

Some riders find it tough to get out in the inclement weather and low light of winter, however, a few key tips and hacks will help you roll through to spring and keep you fit and having fun!

Here are our five top tips for cycling through the winter.

Read More

Indoor Training Apps: Which one is for you?

Indoor cycling training season is nearly here – are you prepared?

We’re sorry to break it to you, but summer is over and the dark nights and wet roads of winter are around the corner. If you prefer to save your bike rides for sunny dry days and clean trails, then indoor training is your answer for when the weather turns sour!

Read More

HOW TO BUILD YOUR HOME BIKE WORKSHOP

No matter what size space you have to work on your bike, there are a few items that you need to have in there to make your fettling easier and more enjoyable. Check out our guide to building your home bicycle workshop!

Read More

HOW TO BUILD YOUR HOME BIKE WORKSHOP

No matter what size space you have to work on your bike, there are a few items that you need to have in there to make your fettling easier and more enjoyable. Check out our guide to building your home bicycle workshop!

Read More

New Year’s Resolutions for Riders

New Year’s Resolutions can last for a week or they can form the habit of a lifetime. Even though the New Year has passed, there’s still time to make a resolution, so check out our guide how to make an effective resolution along with our favourite bike-related goals from past years!

Read More

Road Bike Tyre Pressure: What should I use?

Too high and it feels like you’re riding on huge rocks all day, and corners feel like ice rinks. Too low and you risk getting pinch flats, you wear your tyres out, and it feels like riding through mud. But if you get the perfect pressure in your bike tyres you’ll be faster, smoother, and have better grip!

Read More

C02 INFLATOR 101

Always been wondering what a CO2 inflator is, how it works, and whether it will be appropriate for you and your bike? Let us guide you through this essential cycling gadget!

Read More

Pump or CO2? What’s for you?

Should you buy a CO2 inflator or a bike pump. While either of these tools are going to be great buddies to have in your pocket or backpack on a bike ride, each one has its own benefits.

Read More
REVIEW
5
Please select a valid form.

WE'RE HERE TO HELP

CONTACT ON DARK

become a pro bike tool vip

VIP

WARRANTY REGISTRATION

WARRANTY REGISTRATION
0% Complete
1 of 3