Some food for thought:
Harris Cyclery Flip-Flop Track Hubs!
Harris Cyclery Exclusive!
Versatile Fixed/Fixed Flip-Flop model
These hubs can be used with:
Standard track 42 mm chainline to fit most track frames and many road bike conversions.
Designed with a look reminiscent of the classic high-flange Campagnolo Nuovo Record, with milled flanges with lightening holes.
These hub sets have solid axles with good track nuts,
large serrated locknuts to keep them from slipping.
Smoooooth sealed cartridge bearings, 32 or 36 hole drillings.
Does not include lock ring for fixed gear cogs (but if you leave the lockring off, you can install singlespeed freewheels on one or both sides.)
* 100 mm Front, 120 mm rear
spacing
Click here for specs on Harris/Formula front hub
Click here for specs on Harris/Formula rear hub