I use a mix of Campagnolo, SunTour and Shimano in my 82 Romany:
-Campy hubs with a SunTour 14-32 Winner 6 speed freewheel.
-SunTour Cyclone MkII derailleurs (GT rear) and ratchet barcons.
-Early 90's Campagnolo MTB right crank (Centaur, I think) with Shimano ramped 24-36-46 rings (swift and smooth shifts). 89 Campagnolo Chorus left crank.
-For many years I used a Record BB, replaced by a Shimano Ultegra a couple of years ago.
On the bb and threading, the Mercian is British as the bike is made in Derby, UK. Will any double or triple bb work - like could I use a new Shimano Ultegra triple bb, triple cranks, and triple front derailleur??? Did I read somewhere (maybe Sheldon Brown) that new Shimano front derailleurs are not indexed?
Thanks.....but now thinking about it last few days I might just re-sell the older Mercian and enjoy my other new one. I've got a line on another bike set up for touring already - I might just turn around and re-sell the 1977 Mercian. I'll evaluate it's condition and such once I receive it Saturday.