I picked up a basement-dwelling RB-1 this weekend. It's in good shape save for a few problem areas, one of which is a seized BB. I've only worked at the adjustable cup, but it's going nowhere. Just so I know what I'm dealing with - Suntour GPX, we're talking steel cups, right? If they were aluminum, I might resort to ammonia, but w/steel on steel I go with PB Blaster?

PB blaster and:

https://www.bikeforums.net/showthread...ight=fixed+cup

How hard have you tried to remove the cup? Virtually all the cups I've tried to remove have come off relatively easy if I clamp the fixed cup flats in a vise and turn the frame, even a frame that sat around for 15+ years.

PB Blaster would help of course.

Hope this helps,
cdr

Are you saying that the adjustable cup, not the fixed cup is seized? Have you removed the crank arm? Did you succeed in removing the lock ring? Do you have a pin tool to loosen the adjustable cup?

I'm working on the adjustable first. I removed the lockring but the cup is not moving. I have a pin spanner, but it's not budging and the spanner just chews up the holes on the cup when it inevitably dislodges with some torque.

Definitely soak it with a penetrating oil for a while, maybe even spray a good amount down the seat tube, then work on it over the course of a day or so.

If it still doesn't budge, I've had luck with a punch and hammer on stuck adjustable cups, but it'll do more damage than your spanner wrench. When you turn the spindle, is it very rough? If so, the bearing surfaces are probably shot anyway, making destructive removal an easier choice for you.]

or

Remove the fixed cup first, as miamjim's thread instructs, then use the Sheldon Brown tool on the adjustable cup: https://sheldonbrown.com/tooltips/bbcups.html

OK, so first if there is any evidence of rust on the threads, lay it on the drive side and apply your favorite rust solvent and let it sit for a day or so to let it work. Next, hold the pin spanner over the cup with the palm of your left hand, and give the end of the spanner a series of quick sharp impacts with a plastic mallet or other wide faced object. This should break the bond between the cup and BB threads. If this does not work, we can discuss other ways to remove the cup that will damage it but not harm the frame.

Try to remove the fixed cup using the method in post numbers 2 and 3. If you can remove the fixed cup remove everything else and work on the adjustable cup.

The big bolt method may work.

Fabricate a a spacer from a block of hardwood by drilling a hole large enough to accept the spindle. Use the spindle bolt and a large washer to hold the spacer and tool in place. This should prevent the tool from slipping out of the holes in the adjustable cup.

If the BB is shot, I'd go with the vise method on both sides. With the lockring off you probably have enough of the adjustable cup showing to clamp onto. It would work best to file a couple flats on the cup so the vise has more purchase. Just don't tighten the vise enough to deform the cup.

+1 if the BB is, in fact, shot.

Yeah, it feels pretty shot. Chances of taking it apart and not finding some serious pitting are pretty slim. That said - I don't have a bench vise. It's one of the many things in my moving-out-of-Brooklyn-to-a-house-with-a-detached-garage-or-barn fantasy.

I've used the Sheldon DIY tool on fixed cups before, so I guess I'll just spray it all down with penetrator and then give it a whirl. Maybe I'll get a nice spindle out of it all!

Thanks guys.

The most heroic way of removing a stuck fixed cup I ever saw - welding a piece of steel on it and holding it in a vise!