So I'm doing the 545 mile AIDS lifecycle bike ride next year on a fixed gear bike and I have a 46 tooth front chainring and currently run a 16 tooth cog in the back. I have a flip-flop hub and was wondering what gear I should put on the other side of the flip-flop for going up hills and if I should change the front as well. I've been running this ratio for years and love it for commuting but am wondering what anyone might suggest for a chainring and 2 cog sizes for the flip flop to get the job done and accommodate the diversity of the terrain.