OK, you asked for it... You're retired and only get out 2 or 3 times a week? Where are your priorities? Good grief. You should be out there at least 6 out of 7 days. (Just kidding.) If I can ride like you ride when I'm 64 on 2 or 3 days a week, I'll be mighty happy. Individual fitness and individual potential vary a great deal between each person. You really should be setting goals based on where you are now and measure progress against that as a baseline. You may never reach some of the performance levels of some of the monster riders on this fourm, or you may well find that you can exceed them. But never compare yourself to others. It's a no win situation. I think it's good to ride with faster riders once in a while. It pushes your anerobic threshold, but I wouldn't use it as a regular thing.
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A conclusion is the place where you got tired of thinking. - S. Wright
Favorite rides in the stable: Indy Fab CJ Ti - Colnago MXL - S-Works Roubaix - Habanero Team Issue - Jamis Eclipse carbon/831