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.
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 >>
My bike started recently having a problem where every few hundred meters my pedal arm gets loose and shaky, and I have to stop and tighten again.
I've completely opened and cleaned the bottom bracket and I've replaced the ball bearings (not the cages). The situation has improved, but the pedal still gets loose.
I'm not sure what to try next in order to fix it:
When I replaced the bottom bracket it seemed not too worn out, and only the point where the ball bearings touch on it had lost the paint, and it had signs of fatigue where the crank ... Read more >>
Hopefully someone can identify the wrenches I need:
thanks in advance.
... Read more >>
I have a Origin 8 Adrenaline frame - Info on the frame: 65mm BB Drop?. I bought SRAM red components. SRAM Red carbon TT crankset 130bcd BB30. I'm completely new to bike building. I want to get all the parts together. not sure exactly what BB I need. BB30 but, not sure of sizing. Thanks for your help!... Read more >>
I'm fairly new to bmx terminology so bare with me.
My old bottom bracket and crank was rusted and the threads were severely stripped so I decided to replace them. The new crank, spindle, and bearings I bought are all 19mm and the old ones are 22mm or something. I took the old bearing cups off the rusted bearings to use with my new ones, but they don't fit, so I'm assuming you have to buy new bearing cups specifically for the size of bearing? (I know this is probably a dumb question) And are all bearing cups the same circumference on the outside?
My other question i... Read more >>
Newbie here, so forgive me if I picked the wrong area for my problem.
Kids 16", single speed, coaster bike. Got for Christmas from Wal-mart b/c he LOVES Superman. http://www.walmart.com/ip/16-Huffy-DC-Superman-Boys-Bike/27831881
Worked fine until today! I didn't believe my son at first since he's a little small for the bike. Pedals no longer turn or turn with great difficulty. I can barely move them by hand forward or backward. At first it would work backwar... Read more >>
I've had a Raleigh Silver Jubilee since it was new in 1977. The chainset needs replacing. I have not been able to find a replacement that gives anything like the correct chain line. Can anyone help?
The alternative would be a shorter spindle. The original was a 126mm 5s. I can't find anything shorter to fit the 70mm frame. It probably needs to be about 116 mm. Help?
If a shorter spindle is not available I could replace the existing bearings with a cartridge but I can't find anything 26tpi for a 70mm shell. What would you suggest?... Read more >>
Looking to rebuild the entire drive train on an old frame. To start, I'm looking at the Shimano Tourney A070 double crank set. But I can't make head or tails of the spec sheet I've found for a compatible BB? Shimano's recommendation is the BB-UN26, for which there are at least 5 different lengths (from what I can tell from some ... Read more >>
Hey folks! First post. I'm working on a salvage project, re-building a road bike from an old frame. I want to put a cartridge BB in it, but I need some help figuring out sizing, etc. Disclaimer: I'm terrible with brands, but good with the mechanical side of things; you may have to hold my hand a little through this one.
I've looked at some of the stuff from Sheldon Brown, but it's really going over my head. Or maybe my mind is just saturated... I've been doing a lot of reading...
Anyway, the old spindle was a 3T, which I believe means I'd be best suited picking up a 1... Read more >>