Building up a bike from spares and I have two steel frames to choose from. Both require a 118mm axle BB and, as its more of a spare bike, neither will be built up at the same time. One has a 73mm BB shell, the other 68mm BB shell.

If I buy a 73mm/118mm BB (Probably Superstar ISIS), will it work ok on the 68mm shell with a 2.5mm spacer on the drive side?

Personally I can’t see any problem and there looks like lots of thread on the Superstar BB so I’m not too worried about stripping the threads. Also the non-drive side cup has no lip so it should just be possible to just screw it in a bit further for the 68mm shell.

What have I missed?

all the isis bb we stock are 68/73mm shell(4 brands) and come with the spacer included just dousent say it on the tin but douse on the bb shell so the superstar ones should be fine

Cheers rp16v