I counted the teeth on the smallest sprocket to make sure, and there are 14 as I thought, and the crank says 50 on it. So according to the Sheldon Brown site, that puts me at 22.9 mph at 80 rpm. Going to 13t would make it 24.7 mph at 80 rpm. So an improvement of 1.8 mph. I didn't realize 100 rpm was the goal to shoot for - thanks Lar! The crank is a Sugino ATP btw. I kind of like it and would prefer a 13t freewheel anyway. My goal is to go long distances at high speeds with as little effort as possible, sort of trying to shrink this huge city. Being able to cruise at 25 mph would mitigate the problem of people trying to pass me while in a 25 mph hour zone as well.