I have a pair of Remus carbon fiber cans on my bike, and I have noticed that they never get very hot. Does this mean that carbon fiber is a good insulator, and if so, would carbon fiber belt covers be a bad idea? I just broke my stock belt covers, and although I don't really want carbon fiber replacements, I am considering it as a option.
it's not that it's a good insulator, it is that it does not absorb heat well and sheds it quickly.
the metal parts on the front and back probably get hot, of course, but since CF does function well as a "blackbody radiator" it doesn't keep much heat.