Old bottom bracket removal
 

It had an old, cottered crankset on it. I removed everything but the cups, if I'm naming my parts properly. For the purpose of stripping, repainting (or powdercoating) and possibly upgrading the bottom bracket, I'd really like to get it completely removed. I'm just not sure how. I gave a couple of experimental taps with a screwdriver and a hammer, which is how I removed the headset cups, but I don't want to ruin any threading that may exist in my bottom bracket, although I can't see a way to grab those parts, so it's hard to imagine that they're sitting in any kind of thread. So what's the proper procedure for removing these pieces:

http://www.loominess.name/media/IMG_1348.JPG

From what can be seen I think your intuition is correct, they are press fit
bearing races. If so then it is unlikely you will be able to 'modernize' the
BB, as newer BB assume a standard diameter threaded housing. If the
shell is standard size, it could in theory be tap threaded. The Sheldon
Brown site has standard sizes listed, but an ID slightly under 1.37" and
a width of 68-73mm encompasses contemporary BB sizes, soon to change
however. ("slightly" meaning at most 0.02" under 1.37, and some reaming
may be needed)
If the races are ok, or only a little pitted, best to just reassemble after
cleaning, with appropriate masking of the BB area in powder coating. From
the amount of grease and the bike frame configuration it is unlikely the
bike has gone more than 100mi in its entire life so wear and tear are going
to be low.

The outside of the bike has some bad rust areas including the exposed parts of the bottom bracket assembly, which is one reason I though it'd be a good opportunity to replace the whole thing. I was thinking/hoping that it was the same size as an old one-piece-crank and that this adapter would give me the threading I need. But I guess I need to measure the bottom bracket shell to see if this is really an option. But you're right, apart from the rust, I don't expect much wear and tear on the actual components, so I may end up having to just get some new old parts and use the inside cups as is.

Will it be possible at least to get cotterless cranks to fit this assembly? I'm a bit behind in crank technology, having ridden old bikes with one-piece cranks up until about a year ago. As a result, I'm afraid that I may have damaged the cotter portion of my old cranks during disassembly. It seemed pretty straightforward as I was doing it, but those little cotter pins did not come out looking especially straight.

the adapter you are talkig about should work just fine for you . just use a punch to drive out the old cups . your bb had no treads in it. good luck .

the adapter you are talking about should work just fine for you . just use a punch to drive out the old cups . your bb had no treads in it. good luck .

On further examination, I don't think that adapter will work for me. I think the relevant measurement is the diameter of the bottom bracket. I have bike with an old, one-piece crank, and it's BB has a much wider diameter. The BB I'd like to replace appears to be 4 cm or 1 + 5/8 inches in diameter, but I don't see where that measurement is tracked on any conversion unit.

Basically I'm at the point now where the big obstacle in the restore is my needing to decide if those pressed in cups come out (or if they even can come out) or if they stay in. Is it possible to modernize this in any way? I would at least like to ditch the cottered cranks, because I'm guessing they will be a pain to find replacement parts for, but really I'm just overwhelmed by the volume of bottom bracket info available, and by how I can't figure out how determine if any of that info applies to my current situation.

As long as your bottom bracket is a standard one-piece, you should be able to use the adapter sold by Sheldon. Alternatively, you can stay with one-piece cranks and replace the BB (cups, cones, balls, and all) with a bearing kit that costs all of about $16, also available from Sheldon. A modern crankset would probably really drop some weight, though.

I had to whale on those cups a little to get them to move when I did this. Flood the press fit with some WD-40, support the frame tubes on the ground with some blocks, and use a chunky (1/4") punch. Then really put some momentum into it. Once the cup starts moving, change the place you're hitting so the cup comes out square.

Good luck!

Edit: wait, wait, wait...how can your crank be cottered and one-piece at the same time??? The cotters are used to keep a three-piece crank together.

Yes, sorry for the confusion. This is not a one piece crank. I was thinking the adapter piece from Harris Cyclery might serve the same purpose in my BB, but that was before I noticed that it was not remotely the same size as a OPC Bottom Bracket.

Now I'm trying to evaluate my other options. The bottom bracket shell seems to be about 40 mm diameter, 68 mm wide. The width is easy to deal with as it's pretty standard, but diameter seems to be non-standard. But I really don't know, because when looking at the one hundred and one measurements associated with bottom brackets, I can't seem to see one for Bottom Bracket Shell Diameter.

I'm assuming that if I really spent some time pounding on those cups, they'd come out. But I'm not going to do that if I don't know that they can be replaced with something else. I'd love to replace the cottered cranks, and the whole BB assembly for that matter, but either I have a very non-standard size, or else I'm just not doing a very good job of figuring out all the vocabulary and sizing issues. Maybe there's some Remedial Bottom Bracket class I can enroll in. :twitchy:

http://sheldonbrown.com/glossary.html

there is no better place to learn than at the feet of the master............