tried removing an old ST BB from an old frame i want to “do up” a bit… all was going well, and there was a bit of movement from the BB when it suddenly let go and shattered the teeth (plastic) on the BB…

thoughts?

That’s just a cup, you can pull the whole BB from the drive side and with the load off that should come out.

Might be a good idea to get some penetrating oil into the shell first.

If it’s really tight and you are using an open ended tool on the drive side you can put a penny washer and crank bolt in to stop it slipping out of the splines.

Chisel the bugger out. (Carefully) you’ll be wanting to get the threads chased afterwards mind.

As Neil says. Pull it out from the other side then get a hacksaw blade and carefully cut through the cup (don’t cut too deep!). Then use a slotted screwdriver, or any other tool, to prise the bits of stuck cup out.

Ah, good to know, this is 1st ST I’ve tried to remove… Drive side is stuck fast though, & I didn’t want to be too brutal given what happened on the non drive side!

Cheers

If it’s plastic,it’ll melt out. As said, get it out fromthe drive side, then just melt or carefully chisel it out. Plastic cups can be a pain, but owhere near as bad as seized metal oes.

If it’s really tight and you are using an open ended tool on the drive side you can put a penny washer and crank bolt in to stop it slipping out of the splines.

Remeber to loosen the bolt off as the cu comes out though. If it comes out.

Pour some thin oil down the seat tube and let it sit for a day or two, looks like it’s been in there for a good while.

If you have access to a work bench, vice and the right tool, put the tool in the vice and use the frame for leverage.

all good top tips, and yes, there’s a bench vice at my mum and dads.. lovely stuff 😀

Is the corrosion sticking out a bit right at the end of the thread? That might have stopped the cup enough to wreck it.

possibly…. lokking at the pics (i’m at work right now) i can convince myself either way!!

Bolt thru the BB tool and into the BB spindle to keep the drive side cup from slipping. Remember, drive side cup is reverse threaded!

Use my tool tip to get the drive side out: Bottom bracket tool tip.
Then you can get to work on the plastic cup. In my bike shop days I used to make two cuts with a hacksaw nearly all the way through the plastic and then just lever it out with a screwdriver. Then I would chase the threads with the Park threadchaser. Use lots of copper grease when fitting the new one!

Bolt thru the BB tool and into the BB spindle to keep the drive side cup from slipping. Remember, drive side cup is reverse threaded!

This

As above, looking at the way the splines have deformed on the DS, you’ve been tightening it.