Bicycle Tutor

How difficult is it, and what tools are needed, to change out a bottom bracket?
Dave

Hi Dave,
There are 3 common bottom brackets shown here:
http://www.sheldonbrown.com/gloss_bo-z.html#bottom
Which one do you have?

I have to go look at the bike when I get home. It's a fairly new specialized tarmac, and suspect it is the cartridge type set up. I sure appreciate your assistance!
Dave

To remove your crank arms you'll need this tool:
http://harriscyclery.net/itemdetails.cfm?ID=542
To remove the bottom bracket you'll need this:
http://harriscyclery.net/itemdetails.cfm?ID=518
Once removed, you'll have to replace the entire bottom bracket. Unlike traditional bearing/cup units, the cartridge BBs are sealed, and meant to be replaced rather than serviced. Any good bike shop can match up your old BB and sell you a replacement. I'm hoping to do a video tutorial on this soon. Let me know how it works out for you.

Thank you! What a great resource!
Dave

Hi Alex. I'm replacing a sealed bottom bracket also. Do you know what the torque specs would be on a Shimano UN54? There's nothing in the box telling me how tight to install it.

Tighten it with about 360 inch pounds, which equates to 30 foot pounds, or 40 Newton Meters (Nm).

Thanks Alex. Both sides? The left side is a plastic piece.

Sorry... yes only the metal end. The plastic side just needs to be snug.

Excellent. Thanks very much.