Originally Posted by Ritterview
I'd have thought that once. In May, however, I switched out my alum/carbon Centaur Orbea for a BMC Pro Machine. Wheels are Campy Eurus on both. On my 9.4 mile flat/rolling trip to work, a good time for me had been 32:30 min, 17.5 mph. Now it is 27:59 min, 20.26 mph. The friends who used to drop me on hills are now dropped by me. I didn't expect such a significant improvement, but it is undeniable. It appears to be about a 1.5-2 mph difference on the flats, and greater on the hills.
I think the difference is either 1)enthusiasm, or 2) improving fitness. I could do 10 miles on my steel road bike with 32 spoke wheels, and then on my $6000 TT bike with Zipps and not come up with a 2.75mph difference.