Originally Posted by
bbattle
48-15 is pretty tall; unless you're out on the Bonneville Salt Flats you won't need it or be able to take advantage of it.
This is truth. Having ridden 48/15 all the way to 48/19 I can tell you that personally I prefer 48/17. But right now I'm pushing 48/15 because it's fun to go fast! I don't like the extra stress I put on my knees starting from a stop. I really have to concentrate to start very slowly. Choosing your GI is a very personal choice. I run spd's. Ride mostly with traffic. Most trips are under 3 miles. Most of my riding is fairly flat. With 165mm. 23c.
Usually it's easier to convert your ratio to Gear Inches, and compare things that way.