Listen, today was cold, but it was Defcon 4. Defcon 5 is 15ºF with 25mph+ winds. THAT is my personal limit. I think the coldest temps I've ridden in were about 12ºF. Below that I totally bag it. Fortunately we only get a few days annually that don't get above that mid-day. In some parts of our listening area they get plenty of days like that. And some of these people ride in those conditions. I probably would too if I was confronted with them more frequently. Where there's a will there's a way.