The steepest local climbs top out at a 10% grade so 52/42, 14-28 or 14-26 works fine for me. Also you could go with a crank that lets you run smaller rings. I need to build up a 70s Mercier 300 this summer. I'll run a 13-28 ultra 6 in the rear and a 48/34 using a stronglight 99 crank.