I have a 76 Dawes Galaxy with a (measured) 66mm BB shell. It presently has a 68mm cartridge BB with 118 (measured) square taper spindle. The BB has quite a lot of slop and sounds quite rough. I had it apart today (because I had previously assumed it still had a non-cartridge bearing and it might just need the cup adjusting. I can't get too excited about chain line because I have yet to find a sensible way to measure it with the tools I own and this is a 5 speed block with 3/16 chain so not critical to my mind, however, I noticed that the inner ring (52-42 double) is rubbing against the chain stay. This is partly due to the sloppy spindle but I suspect also that the chainset is too far inboard. so what are my options?
Buy the same BB but shim out the RH sleeve. Presumably an old BB lock ring of up to around 2-3mm thickness might do this but would one be as thin as that and where would I be likely to source one anyway?
Buy a 68mm BB with a longer spindle but which to go for? 122.5? 127.5? I am right in thinking that I should aim for longer by double the amount by which I want to shift the chainset outwards?
Something more exotic I haven't thought of.
I like the bike but can't really justify spending much money on it as a backup/runaround. If it had been just a case of swapping out the BB like for like I would have been happy to grab a cheap and cheerful one for around a tenner but now I am worried that I need to shift the chainline too and so need something slightly different
