I've just bought a Specialized Secteur elite, and am really pleased with it. Been on a couple of shortish rides so far (35 & 45 miles) and have noticed that I feel the bumps in the road much more than on my Specialized ttricross. I was expecting that; however, the elite has come supplied with 23C tyres, not the 25C mentioned in the specs. I was wondering if changing them would make much of a difference in damping vibration and bumps. At the moment I'm planning to stick with the 23C until I need new tyres and then getting a set of 25C to compare. Has anyone else done this (or the other way round?).