tsl thanks for the offer but my focus is really more on changing out the cogs on the cassette. I can see how my original post is a bit confusing. I was originally being told by fellow riders that I should go to a compact. Then I got the alternative suggestion of just changing the cogs from 12-25 to something like 14-26. I think what got me thinking about all of this was the fact that I don't use the 53x12 or 53x13 very much. I was also curious to see what kind of gearing I could turn at a reasonable rpm now that I'm 66.