Yes, it's about gearing. I searched and read old threads, but I think this is specific enough to be worth asking.
I'm thinking about racing single speed for the first time this Saturday. The only option I've got right now is 46x18. (Stop laughing, this might work.) I ride that ratio fixed on my commute, but I've got a freewheel that I'd be using for CX. The course I'm thinking about using this on is completely flat. It's an old golf course. I raced there last year, and the only variation in elevation, literally, will be a few trips up and down tee areas.
I fully expect to finish DFL. The single speed guys around here are fast, and I'm mostly considering racing in that category because of a schedule conflict. I would, however, like to avoid DNF because of my legs falling off.
So, my question is, if you were in my position, would you give it a try with the 46x18 gearing or would you start scouring the LBS's for a smaller chain ring?