Originally Posted by SlimRider

Hey there Beginnerbiker!

For most modern-day carbon frames made by reputable carbon fiber frame manufacturers, the carbon frame will be extremely durable in terms of fatigue life. Carbon fiber on carbon frames is anisotropic. That means that the stress inacted upon the individual fibers will act along the lines of a specific plane. Steel on the other hand is isotropic and the force inacted upon steel acts in all directions.

Therefore, the effective fatigue life of a carbon frame is totally construction dependent. If the carbon fibers are not layered and applied properly, catastrophic failure and a much limited fatigue life will most likely be realized.

Riding an aluminum bike continually will eventually result in a failed frame, no matter what. However, riding a carbon frame continually is quite feasible as it has an infinite fatigue life right along with that of steel.

OTOH steel and aluminum can both absorb a specific amount of energy upon impact without deformation of the surface of the material. Carbon tends to be less resistant in terms of impact resistance. One should be quite careful, not to place a CF frame in the path of a projectile. One should also be careful not to drop a bicycle with a CF frame.

- Slim