[gohm]

They have done studies of gases and old fashion air actually works the best in tires because it is cheap, easily available and has great properties dealing with compression and heat. Thick rubber tires would decrease the tires ability to absorb bumps, transmitting more to the bike causing increased unstability in the steering geometry and a rougher ride for the user. The suspension system and wheel would also get more force passed through it. Even though thick, your tire is still filled with a gas which could still get punctured though maybe not quite as easily. Also thicker tires would have less grip because it would take much more heat from friction to warm them up to proper operation temps for optimal traction ability.

By carbon fiber frame are you talking about the wheel/rim?