I have posted this in the Mechanics Forum also, but I thought you guys might be able to help too.

I just picked up this old frame that I am planning to convert. The BB will hardly turn so I am going to replace it from the get-go. Can anyone tell me how to remove this type of BB from the frame? Also, will this frame accept a modern type bottom bracket? Thanks.

Take off the lockring with a lockring tool, or carefully with a screw driver and hammer. Then unscrew the cup with a wrench.

is that an old raleigh?
it kinda looks like one of their old 26 TPI BBs. (if so you're virtually screwed for new BBs - see sheldon for info)

if not, you just need a lockring tool (right threaded lockring) remove that, then you should be able to spin out the removable cup by hand or with a big wrench. then you can have fun with the fixed cup.
if you're lucky a big wrench will do. if you're not lucky then you'll need a fixed cup remover - see your LBS or sheldon for a homemade version

It is actually an old Schwinn. Am I still "screwed"?

oh, not screwed. it should be a regular british threaded BB then

you might be screwed for stem size though......but likely not.

don't the electroforged schwinns have a giant bb shell that needs the insert-thingy (can't remember what it's called) that will allow a normal bb to be threaded in?

yes, varsinentals have ashtabula cranks.
that picture, however is not of an electroforged schwinn, nor of an american BB

Well, didn't I get lucky. I've got a Schwinn conversion with the weird cranks, and the weird stem. I can't even run modern pedals on it.

good point.

/wasn't paying enough attention.

I made a fixed-cup remover following Sheldon's advice, and it works like butter. Cost $1 at the local hardware store.

Even you have trouble finding a cartridge bb for the frame, you may not be so screwed. Once you get the thing open, scrap all the bearings and have a look at the insides of the cups - if they're not grooved or pitted, you might be able to just clean 'em out and put in new grease and a new set of ball bearings. I just did this with an old French bb and it is running like new now. I followed Sheldon's advice and traded the bearing holder (that plastic thing that olds 7 ball bearings) for loose bearings (11 per cup). I also scrapped the old axle (which took annoying cottered cranks) for a newer, square taper sort. Maybe you can do the same.