I have a Volvo (automobile) with a roof rack system.  I have been using it to transport my Soloist Team for more than 2yrs.  I just contacted the dealer to replace some mounting hardware as it is starting to pit from the elements.  when doing this I noticed Volvo states not to use the fork-mount system for a bike with a carbon fork.  Can anybody tell me why?  My carbon fork is Oval Concepts R900 road fork that is carbon fiber but with alloy drops that won't crush.  Is volvo concerned with road debris hitting the fork and damaging the carbon fiber? 

I may have this wrong but I think I read that its to do with the possibility of snapping off the tip of the fork as you lift the bike from the rack. The danger is that as you reach on top of your car and lift the bike you fail to lift it perfectly straight up and end up lifting it up and towards you. This would bend the fork dropout in a way its not designed to move. As I understand it carbon is particularly intolerant of being stressed in directions in wasn't designed to work in.

Just be careful lifting it straight up and down into the fork mount. Nearly everyone I know uses a fork mount bike carrier and almost everyone has a carbon fork as well. I have never heard of a problem that wasn't due to human error - such as only clamping in on side of the fork.

I probably don't take the offramps as fast when I have my bike on the roof either. :)

Thanks all.  I see where a bad mount could do some damage.  Especially with an suv0crossover like I have.  It is taller and i can't see when loading the bike.  But with a Cervelo frame of any material I can't see using any other type of carrier for roof mount than a fork-mount.  On my Jeep I have a trailer hitch and use the Saris Thelma.  That is an awesome carrier. It grabs the wheels only.