10. How to Replace a Cartridge Bottom Bracket
Demonstrates how to remove and install a sealed cartridge bottom bracket.
This tutorial will demonstrate how to remove and install a sealed cartridge bottom bracket, found on most modern bicycles. You’ll need to remove both cranks first, so be sure to refer to last week’s crank removal and installation tutorial before you begin.
A cartridge bottom bracket usually has two main components. The cartridge contains the sealed bearings and spindle, and is usually threaded into the right (or drive side) of your frame. The lockring supports the opposite end of the cartridge and is usually threaded into the left (or non-drive side) of your frame.
Remove the drive side first, using the lockring tool and wrench. On most bikes, the drive side has a left-hand thread, so you’ll need to turn your wrench clockwise to loosen. Once the drive side is removed, the non-drive side should easily loosen and unthread by turning counter-clockwise.
Before installing the new bottom bracket, carefully clean the threads on the inside of your frame, and then apply a thin layer of waterproof grease to the threads on both sides of the frame.
You’ll notice that most bottom brackets have an ‘L’ and ‘R’ written on them to assist in installation.
To install, first thread the new lockring part way into the left side of the frame by turning it clockwise. Don’t tighten the left-side yet.
Thread the cartridge all the way into the right side of the frame by turning it counter-clockwise. Tighten it with about 25-30 foot-pounds of pressure (300-360 inch-pounds) using a torque wrench. Torque specifications vary, so it’s a good idea to check the manufacturer’s website for their exact product specifications.
Now you can finish tightening the left side clockwise until it is nice and snug.
I am trying to restore an old 1955 Triumph that I bought at a car boot sale. I was removing the bottom bracket today and have been having a problem removing the lock ring. I was using a hammer and punch to turn the lock ring (it was very stiff). Once it was loose I managed to remove it almost completely before it got stuck again. When I resumed using the hammer and punch I ended up just loosening the bracket cup which has now come free with the lock ring still attached.. I can get the cup back on but the lock ring doesn't go flush and I am concerned it will not be properly se... Read more >>
Hi, I just bought my first fixed gear bike last week but yesterday the bottom bracket loosened. I went to the closest bike shop and asked if they have a tool/wrench for tightening it. I showed the photo of my bottom bracket and i was told that this type of bottom bracket is not suitable for fixed gears. Do I really need to replace it? I'm still a noob regarding bike parts and I'm having second thoughts about replacing it.
Here's a photo of the part of my bb that got loosened:
... Read more >>
Hi guys. I'm new to these boards. I learned how to fix / maintain my jetski and scooter on message boards so now I'm hoping to do the same with my bikes. I have a mountain bike
This one -
(Cheap bike but I like her)
I know that I need to replace the barrings in my bottom bracket. I want to just replace everything since I have all new parts un... Read more >>
I just want to make the point that I am only 16 and a beginner. My situation is that I have bought a frame and fork from ebay to make into a single speed bike.
I have got into some trouble with identifying the bottom bracket but think that I may have chosen a suitable bottom bracket.
I don't know the model bike, only that it is a Raleigh that I think may be from the 80's. But I have little to go on.
The Bottom Bracket shell is 70mm. But this is the confusing part. I think the internal diameter is 34.5 mm (or around there). I have a bottom bracket cup - SM-BB70 -... Read more >>
lately I've been hearing to a clank sound while pedaling, but on the right pedal. At first, I thought that the pedal was the problem. But yesterday I realized that the issue was that the bottom bracket is loose.
I removed the allen bolt and this is how the bracket looks like. (see attachment)
Do you guys know what tools I need to fix that?
After watching some youtube videos I thought I needed a Crank Puller Remover like this one: Read more >>
I apologise if this has been asked before.
I would like to change the BB on my wife's Mountain bike. At the moment it has cup and caged bearings with a square tapered spindle.
Is it possible to replace it with a cartridge type one.
Neil... Read more >>
First post on the forum, but I've been reading around for the last few months while I built my modified Schwinn OR2 700c electric bike conversion. I've done a little homework, but i'm really looking for a bit of advice before i pull the trigger on part orders:
After some decent overhaul to the stock bike, I am now hearing some clanking sounds when pedaling. I've checked the chain for any tight links and just did a thorough cleaning of the chain to see it that could have been the cause. At this point, i'm convinced its an issue with the BB.
After ... Read more >>
I have a schwinn sidewinder I bought at walmart, and may need to replace the bottom bracket. I believe I will need a crank puller, at the very least, and some sort of specialized tool for the bottom bracket itself (maybe). What do I do to get the correct bottom bracket for my bike?
It's an OK bike and gets me where I want to go.
I am mechanically inclined, and do some of my own auto repair work, but I've never done much for my bike other than replace the innertube.... Read more >>
Hi there ,
Ive been given what I believe to be a peugeot ph8 by my uncle . Ive narrowed the year down to somewhere between 79 and 83 .
The serial number is 0931716 PH8CE 60.
Here are two pictures of what I think is the exact same model except my one has cottered cranks .
Read more >>
Is there a good way of knowing what size of BB your bike takes, without having it at hand, and not having the specs from the manual.
I would like to get the tools and part at the same time to avoid repeat trips to the bike store, if I can help it.... Read more >>
I am in desperate need of some assistance here.
I bought a Shimano Ultegra compact crankset to be fittet on my Specialized SL4 Pro Tarmac - 2012.
I want to replace the bottom bracket as well - but my question is:
Would a Shimano Ultegra BB6700 fit my Specialized bike - or would I need some sort of adapter or something like that?
I seem to be stuck in the BB jungle and does not seem to get the right answers when I google around.
Looking forward to hear from you experts.
Thanks in advance.... Read more >>
I'm thinking of switching out my old Ultegra crankset with an FSA Energy BB30. Will I run into any problems with compatibility? Other than the FSA, my bike would be Ultegra 6700. Thanks!... Read more >>
Hi All -
I'm new to the BicycleTutor Forum and having a hard time finding a replacement for my Chin Haur BB. I have removed the BB from the bike frame and not able to locate the correct BB. I have been to the Sheldon Brown website and I'm unable to understand that busy website. In the process of removing the BB, I broke some teeth off the crankset so I will need a new BB and Crankset.
RFJ6... Read more >>
Is it possible to damage the threads of the bottom bracket shell while undoing the BB?
I'm pretty sure the bike shop would have done it while putting the bike together, but if I can check it's not possible (very unlikely) to damage it while lossening then I'll feel more comfortable complaining til they fix it.
Oggy... Read more >>
Looking at new frames and they all have either BSA or BB68 spec'd for the bottom brackets. Which of these would accomodate an old Shimano UN73 sealed bb unit with English threads? Can't afford new components and a new frame. Thanks.... Read more >>