High quality cro-moly frame
Road bike geometry (73/73 angles, 70mm BB drop, 45mm fork rake)
Longer chainstays (43-45mm)
Canti braze-ons
Road bike top tube length
Clearance for 50+ mm tires
Vertical dropouts with 135mm spacing
I'd set it up with a 3 x 9 drivetrain, V-brakes and Schwalbe Big Apple tires. I'm undecided on wheel size (currently have 700c) but it would basically be a modern version of the Bridgestone XO-1. This "ultimate" bike is based on the Handsome Cycles Devil I'm currently riding, which meets several of the criteria I listed. If it had just a little more tire clearance it would suffice as I can live without the vertical dropouts (but would be nice) and the higher quality tubing.
