Mike, as a fellow numbers freak, it's great to see your methodology. Here's what I do: Decide what my top gear and bottom gear rations will be, based on riding style and on hardware constraints, like what do I have in
the toybox? If there's a convenient choice of chainwheels (i.e. I have a 53/39 and don't want to change it out), I pick the small cog that will ...