As a preamble, I've read a lot of forum posts about groupsets etc and haven't quite found the answer - also my frame is a bit eccentric hence this post...
So, basically I'm wanting to install a modern-ish groupset on my '85 Bob Jackson road frame...which is currently running single-speed.
Got a few questions. Obviously I know it's easier to buy a whole groupset so everything works perfectly but there's always that cash flow problem!
There's also a funny thing with my bottom bracket- it's 65mm wide...Obviously it must have been 68mm wide at some point. I've got a square taper bottom bracket currently installed and both cups/threads stick out either side a bit, but my mechanic said it should be fine - seems fine anyway.
So I'm looking on ebay for a groupset, doesn't matter if its shimano or campagnolo...9 or 10 speed. But the issue i'm thinking is installing BB's like hollowtech/new campag outboard bearings on a bb shell which is a bit odd like mine could be a problem. Is it easier to stick with the square taper that i've got (putting in a longer spindle obviously) and use 9 or 10 speed campag cranks which'll fit?
Or will hollowtech fit with some spacers and I could then get a shimano groupset?
OR (final or) use campag crankset (with the square taper) and have everything else shimano? Would that work?
Back in the day 65mm BB were used on some track bikes for lower Q. I'd just use some spacers. For a ULxx style BB like you show in the picture, I'd use 1.5mm on the drive side and let the other side stick out an extra 1.5mm.