Would doing this just make it slower or harder at take off or is it actually harder to pedal at a certain rpm? I currently have a Trek Earl with factory 44/17 and was thinking about going 44/15 or 48/16. My area is pretty flat and would like to cruise a bit faster on the flats and not overpedal going downhill. I'm not small so power won't be an issue. Comments? Witty banter?