Bicycle Mechanics - replacing cup and cone bb with a cartridge

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.



PDA
Philatio
05-12-06, 02:00 PM
I feel like this has been probably been covered, but I've been reading through old threads for an hour or two and just wanted to clear some things up. This is on a 1986 centurion.

I need to replace my BB. So this is what I think I need:

-a crank extractor to get the crank off
-a spanner to remove the fixed cup on the bb (can I do this with a hammer and screwdriver or similar destructive method? I don't need the old bb)
-do I need anything to remove the other side of the bb?
-a splined bb install tool to get the new bb in

am I missing anything?

The Great Stonk
05-12-06, 02:15 PM
sounds like you have everything coverd...

just make sure the cartridge is the correct length.
BryE
05-12-06, 03:01 PM
-a spanner to remove the fixed cup on the bb (can I do this with a hammer and screwdriver or similar destructive method? I don't need the old bb)


Vice grips can be handy for this operation, but be careful or you may scratch the paint on your bottom bracket shell.

Landgolier
05-12-06, 03:29 PM
I think you have the fixed and adjustable cups confused. The fixed only requires some sort of wrench, adjustable or otherwise (I realize this is called a spanner by brits and certain tool geeks, but he was talking about hammer and screwdriver as a substitute, and that wouldn't get you far on a fixed cup). The adjustable side requires a lock ring tool, set of channel locks, large set of vise grips, or whatever to get the lock ring off if you don't mind messing it up a little. Hammer and screwdriver can work in a pinch, but penetrating oil, 30 minutes, and a set of channel locks should do it. You don't need the pin spanner (which is what "spanner" usuall means on a bike) or anything for the adjustable cup once the lock ring is off, it should come out pretty easily, and if it's stiff you can give it the penetrating oil and channel lock/vise grip treatment as well. Extreme cases can require other methods, but that's not worth worrying about for now.

Don't forget stuff for cleaning out the BB shell, there will be plenty of guano in there! You should also have the BB shell chased and faced while you're in there if it's a bike you care about, and it's not a bad idea to use a torque wrench when installing the new BB.