Check Carbon Frames and Forks for Hidden Damage

Carbon fails differently from metal: an impact can leave damage below the surface that the eye can't see. Look closely at the top and down tubes, where car and roof rack clamps can crush carbon, and at the seatpost clamp slot, where a small crack can turn and run horizontally around the tube. Lift the bike a few inches and let it drop, listening for rattles or clunks from inside the frame or fork. Tap suspect areas gently with a coin and listen for a change in sound. For an expensive carbon bike, or whenever you're unsure, a carbon repair specialist can check the frame with ultrasound before you pay.