Well I’ve got another one
Just a routine strip down with intent to clean the bike up and rebuild it.
This time it’s, I believe, an XTR level UN90 BB or similar in an alloy frame.
Neither cup moved at first attempt, so I bolted the tool in the vice for a proper go.
The non drive side cup (metal) split
so now the tool won’t work at all.
Took to the drive side, and after a little bit of strain it started to turn
, and it wound all the way out.
But sods law, only the cup came out, so the outer casing of the bb remains firmly bound in against the inside of the non drive side cup.