I had carbon fiber protection on my yz-250f. I dropped the bike and a rock punched a hole directly through the carbon fiber and into the water pump housing ruining a good day of riding.
Carbon Fiber is terrible in resisting punctures. That is what kevlar was made for.
If the Carbon Fiber protection does not have a kevlar layer in its makeup I would not consider it for engine protection and, even then, would be a little hesitant. The Kevlar works by giving a little and not breaking. The stock engine covers don't give at all, they just break and they are directly behind the kevlar.
With that said, I have the G-it engine guards.
Uller screwed with this post 10-09-2012 at 05:11 PM