Today I fixed another mystery flat tire (pinhole in the tube on the rim side) and lowered the gearing in my Motobecane Messenger utility fixed gear by 11gi from 67gi to 56gi. Now I can get up a short 22% grade hill with a 40 lb load in my saddlebags w/o having to dismount and walk. It's also a lot easier to get the bike rolling from a stop.