I was talking to my LBS guy and he was talking about the Giant TCR Alliance and how it was a really nice bike for the money, good parts, ride....etc. So later when I got home I looked it up and saw that it has a Carbon/Alum frame which I thought was interesting, but what part is carbon? Or is it carbon over alum? Not sure how it works. I wanted to take one for a spin but he doesn't stock any Alliances at the moment, don't know if they sold out or what. If someone could enlighten me that would be great.