I'm with Aaron (wahoonc) on this. For practicality and minimizing hassles traveling with a bike, I'd go with a Brompton. They have 16" wheels, fold small enough to fit in a 62" (h + d + w) hard suitcase that can be airline checked baggage without oversized/overweight surcharge, yet unfolded have virtually the same contact points as my road bikes.

My M6L six-speed Brommie weighs 28 pounds, and the hardcase with the bike inside weighs 45 pounds.

It can even be checked at the gate without the hardcase like a stroller or wheelchair as it folds small enough to fit through most of the TSA screening machines.

Folded in suitcase:



Ready to ride: