While it is impossible to list all of the scenarios that can cause damage to a carbon fiber part, below are a few examples. If you experience any of the following, stop riding your bike immediately and take it to an authorized Trek retailer to replace the damaged part:• You hit something in the road while riding - a curb, guardrail, pothole, parked car, or anything that causes the bike to stop abruptly.• An object becomes stuck in the front wheel, causing the bike to stop abruptly.• You get hit by a car or truck.• You have crashed your bike and it does not feel or sound “right.”• Your bike is in a roof rack when you drive your car into a garage. Of course, your specific scenario may be different. Remember, any carbon bike part has the potential to be damaged by a crash or impact. There are tests that can help determine if a carbon part has been damaged, but here is the bottom line: if your carbon frame, fork or part has been potentially damaged and you have any doubt about its integrity, you should replace it.