At the amateur level, bikes are always customized by the rider to some degree. Teams are usually sponsored by both a manufacturer and a bike shop, so riders hav

At the amateur level, bikes are always customized by the rider to some degree. Teams are usually sponsored by both a manufacturer and a bike shop, so riders have a good source of discounted components. It's not uncommon for them to strip the bike down to the frame and rebuild it the way they like. The manufacturers also ask for feedback on the frame designs and tweak them every year. I can't imagine things are much different at the pro level.