Quote Originally Posted by MarieV View Post
Jolt, I'm probably only 1-2 mph faster on my carbon bike than my steel bike. On a typical 100 km (~65 mile) ride I probably average 11-13 mph on my ~20 lb. steel bike (Bianchi Eros Donna) compared to an average of 12-14 mph on my carbon bike. So I'm only a little bit faster on the carbon bike, but because it's also much lighter and more responsive, I'm usually a lot less tired after riding the carbon bike compared to the steel bike. I probably wouldn't be able to do century rides on my steel bike, but I'm usually OK after one on my carbon bike.
This is precisely my experience on my Carbon road bike vs. my Ti CX bike with lightweight wheels and slick tires. There's still probably a 4# difference. It doesn't seem like much, but it's astounding how much easier it is to get the carbon bike up to speed and keep it there. And the geometry on my CX bike is just...weird on the road. I don't like it when I'm riding in a paceline, because the steering does not inspire confidence at speed when on someone's wheel. On gravel it's wonderful, though.