I've been doing bunches of shorter rides, usually no more than 30 miles, on my single-speed lately. Today I set out to do another quick ride, but kept seeing more and more inviting roads to ride, and ended up with 70 miles by the time I got home. Needless to say, I'M HOOKED! I haven't had a ride that was this fun in ages. I enjoyed the ride way more than any geared long ride I've done because I wasn't trying to push a hard gear the whole time, which seems to be a natural impulse for me when riding gears - I can't just spin and relax.
So now I'm curious, what gearing do you all ride on your SS/FG rigs? I rode a 39/18 today, which felt incredibly easy in the beginning, but was comfortable at the end of the day. I'm thinking a 17 would be really nice, maybe a 16 if there weren't many hills or headwinds. What factors do you use to determine what gear you intend to ride?