Originally Posted by
catadromous
-23 this morning with windchill -45. I put my bike in my van and drove to work, where I park about a mile away cause it's free. I got on the bike and was doing fine untill about a block from my work. My freewheel started freewheeling in both directions and I walked the bike the rest of the way. I'll see if it will hook up on the way home.
The pawls on your freewheel aren't engaging. It's happened to me too in extreme cold. That and other funny things can start happening when riding at those temperatures.
I don't have a fixed gear mountain bike, but IMO that is the way to go if you can handle the commute on one and you are going to be subjecting yourself to those kind of temperatures routinely. Almost nothing there that can immobilize you if it freezes.