Also, if you get a 14 tooth cog on the other side of your flip hub, you can use 46/15 for warmup and 46/14 for racing since it is equivalent to a 49/15. That way you don't have to change cogs or chainrings at all. Just undo the hub, flip it over, and you are ready for racing.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter