Originally Posted by John_V

There may be several reasons why your enthusiast (avid) cyclist friend is slow. Maybe he was as fast or faster than you, at one point, but hasn't ridden in a while because of some illness, injury or personal reason and is now getting back into it. If you don't want to ride with him, just tell him the truth and leave it at that. If, on an occasion, you still want to ride with him, explain that you are training for a special ride and that you really need to go faster than what the two of you have been doing. Tell him that you need to ride with faster riders on your long ride, while training, and that you will be happy to ride with him on a different day. Just remember that you are him to someone that rides faster than you and they may not want to sacrifice their ride waiting for you to catch up.