Love that Peter White website! Also found Hostelshoppe.com has great info and charts on gearing (they even give the related mph for several cadences at each gear!). I was able to put in several chainring/cogset combos and printed them out. So now i am in the process of comparing them. I want to see if I can sacrifice a couple of high gears and gain a few low gears... wanna get stronger and go faster!