Originally Posted by
SquidPuppet
Your frame has nothing to do with determining what length bottom bracket spindle you need. Spindle length is dictated by cranks choice.
Select whatever single speed or track crank set you like. The manufacturer of that crank will indicate in their literature what length spindle to use in order to achieve a ~42mm chain line.
SquidPuppet is generally correct about matching the bottom bracket spindle length with what the maker of that crankset's specs for it but most, if not all, of us have heard "horror stories", especially on unusual conversions, about guys buying a BB with the "right" length spindle for a particular crank and for whatever reason...the assembly doesn't work right with their bike.
Originally Posted by
howieleem
Hi. Sorry the rear dropouts measure exactly 107mm so I guess they will go to 100mm or 110mm.
It may not be part of choosing a BB for your bike but I find your weird rear spacing interesting. My recollection is that 110mm was for for older track, coaster brake and other single-speed hubs, while 114 was 3-4-speed and some IG hubs...