I personally don't want to go to a triple. I've been riding on a double since I was 12 years old, so I'm sure I can handle it now. Right now I can make it up all the hills I did before, just often as slow as 6 mph and 50 rpm, which I'm sure will improve. But I do live in the hills and the 12-23 just isn't cutting it. Since I think my RD is a short cage, does anyone know how big of a rear cog I can get away with?