what I did was keep trying different combos until I found one I liked, that felt right to me. I finally ended up with 42/15. no hills here though.
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"Think of bicycles as rideable art that can just about save the world". ~Grant Petersen
Cyclists fare best when they recognize that there are times when acting vehicularly is not the best practice, and are flexible enough to do what is necessary as the situation warrants.--Me