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.
Has anybody else ever worked with this? I have installed the bearings which went into the frame by hand and are straight, but whenever I get to tightening the cranks it seems to bind up and there is no way that I will be able to get to the recommended torque level of 48nm. The cranks have the correct order of wavy washer then seal on the drive side and just the seal on the non drive side. The amount of torque I can get it to is about 15nm and there is no play at all.... Read more >>
Good afternoon internet hive mind. A friend has inherited a bike that has a wobbly bit somewhere inside the bottom bracket. I'm taking bits from old bikes to cannibalise into a new one to make it rideable and to be honest the whole thing is a great learning experience for me anyway, but I've hit a problem. In the past I've removed the bottom bracket with the correct tools, then to remove the bit that contains the ball bearings I just use an adjustable wrench to unscrew it. On this bike it isn't nice and hexagonal shaped to allow a wrench to grip properly, it keeps sliding off. It looks like so... Read more >>
Just replaced my bb sealed unit. Taken it for a test ride and it seems really stiff any suggestions to cause. Doing a long charity bike ride Sunday and need to sort it before then
Any advice great fully received... Read more >>
I had some problems on my MTB suntour BB recently, first it made some noise, than it started wobbling, so I decided to replace it. It is a 68/122.5 sealed square tapered BB, so I bought the same thing just a Shimano.
I tried to remove the non drive side, no luck it is stuck, I tried to remove the drive side and it came off very easily, the sealed BB was open, the ballbearings rolled out and the plastic ring that holds the ballbearings in pl... Read more >>
Hello all, I hope you can help me out here, I have a Jamis Beatnik single speed bike 2015
the cranks have a lot of play in them. I have tried tightening the lockring on the NDS as it was quite loose.
but it makes no difference at all. Do I need a new BB I was thinking of a shimano sealed cartridge type but
the actual spindle size of my bb 116mm and shimano don't do that size only 115mm or 118mm can you help?
also do I need to take of the cranks to tighten it properly?
many thanks if you can help?... Read more >>
Her I have a shimano BB - UN52 68 BC 1.37 x 24
The frame is threaded. I was just wondering if I have too stick with square taperd or can I upgrade ? Also what are they key numbers in that description for size etc. ?
... Read more >>
It seems like there's no spindle in bottom bracket, because when I try to take off the crankset with removal tool, then there is nothing against the bolt to push and you can see hole through the bottom bracket. Do you understand me? How should I take off crankset if there's nothing I can push against?... Read more >>
Ello. I was just wondering if anybody knows what the torque settings for the cups and crank arms are on this? A piece of paper within the packaging states to consult the manual, but there isn't one, not even online (that I can find).
Also, which way does the cartridge fit onto the bike? As you can see in the image below it says.#
Does that mean that the side without the metal threads goes to ... Read more >>
My old cheap 2003 Huffy bike has this BB:
Since I actually enjoy riding this cheap "beater", I plan to do some upgrades. I want to remove this BB and convert to a square taper BB (because I am now familiar with SqT BB's, having replaced two of them on other bikes), and I will install a new crankset compatible with the new SqT BB.
-... Read more >>
Hi, I have a normal mountain bike bought from a department store about a year ago, I've been hearing a lot of creaking noise recently and found out that the spindle is wobbling a great deal ( not just the crank arms ).
After watching some videos, I discovered that the remedy seems to be simply adjusting the hex cup on the non-drive side, since I recognize it to be a ball & bearing bottom bracket.
I don't even need to take off the crank arm, my wrench fits in the gap between as you can see from the picture.
Read more >>
Has anyone tries the bolt and locknut method for removing the left side bottom bracket bearing race cup. hope I got that right? i was able to remove the right side. the bracket is the spline wrench type like a free wheel but the tool fits in only 1/8 of a inch.
...... method is to get a 2" bolt, 5/8th diameter, and about 14 lock washers, a large flat washer and a nut to fit the bolt. then you put the bolt with all the lock washer slid onto it and insert it through the right side of the bottom bracket and out the middle of the left frozen bearing race cup I want to remove. them y... Read more >>
2006 Gary Fisher Piranha BS:6102 crank is a fc-m410
Hi i am new here and need a lil help with my bike i just brought to ride to work on, so when i ride i can feel that the crank bearings need replacing or bottom bracket i am not a bike mechanic, and i am struggling to find what bottom bracket i need to fix this issue, any help will be much appreciated thanks for your time and reading,
Adam.... Read more >>
This is about a bitchy seized and insisting bottom bracket. It is from a 85 german hercules bike and the BB is the standard german F.A.G by that times. http://de.wikipedia.org/wiki/Innenlager#mediaviewer/File:Fag-g.jpg well in my case both plastic sides are broken after trying to remove it. I have the appropriate tool but the BB was seized so it's jammed and broken in there. After reading some forums I got a soldering tool to melt the plastic. It works. The bearings are e... Read more >>
Hi. I am trying to renovate a Viscount Aerospace and am having difficulty with the bottom bracket. The shell is normal 68mm, but has pressed in 35MM bearings (not BB30) and a 119 mm spindle that (obviously) passes through these bearings.
Bearings are easy to find, less so the spindle! The spindle has been damaged (not by me) and is useless. I have tried all the places I know to find a spindle, but cannot locate. So am toying with the idea of fitting a sealed bottom bracket (the damaged thread, repair type, as the shell is not threaded and too thin to try and thread). Has any... Read more >>
hey I have a 1973 Schwinn Continental frame and fork. I ordered it off of eBay and it did not come with a bottom bracket or anything. How would I go about deciding which bottom bracket to buy?
thanks... Read more >>