Originally Posted by
Chili Cheesy
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It was old Nottingham threading with cottered cranks. The BB is already refaced. It's ready for the standard, common BB's of today.
Ok, I wanted to make sure you did not go too far with your plans, only to have them dashed later. But you already got that problem fixed.
Some of teh Nottingham bottom bracket shells were wider than 68mm, but narrower than 73mm. If you find that it is too long to put a 68mm bottom bracket in, you might be able to use spacers to make a 73mm bottom bracket fit. But I would try the 68mm first as it might still work ok.
I can't imagine ever needing to carry an extra UN55, I have one on my expedition bike, it is adequate for long distance touring.