Originally Posted by Wogsterca

Are you sure that a wider tire has more aerodynamic drag. Bicycle tires have a rounded profile, a larger tire might offer a more aerodynamic (rounded) profile to wind, because the tire is more rounded, rather then being a flatter profile on a 23mm. There is rolling resistance, but IIRC that's not affected by tire width as much as once thought, but is more a combination of tire pressure, sidewall stiffness and load. Ride harshness also has a lot to do with tire pressure, if you run a 23mm tire at 130PSI, it will ride much more harshly then the same tire at 110PSI.