I'll be 57 in a couple weeks and I began racing two years ago and now race with the Cat 4's and Masters. I started with the goal not being last or embarrassing myself. My first couple races were eye opening and quite the learning experience. Race speed varies by the course, number of riders and how the thing plays out. Sometimes during races the pace would be ridiculously low then go turbo in a heartbeat, other races had an early break and the rest of the guys just rode a hard group ride with a sprint for nothing at the end.
Where I live the Master's races mostly have Cat 3's and 2's with a few 4's like me. The competition is greater in the master's races than the Cat 4 races but the average speed for the race would usually be lower than the Cat 5. It's the attacks that you will need to train for to be successful in the races. If your race is a Master's 55+ Cat 5 race your competition will mostly be new racers like you. Try to find the results from earlier races to see how many racers competed and how the finish was. As for race speed I've done road races with 21+ mph up to a flat 52 mile circuit race last summer with a 27.4 ave.
Good luck. You have plenty of time to get ready.
Last edited by Allegheny Jet; 02-08-10 at 08:55 PM.