My headset tighten up this morning, I could still steer but it was moving freely. Same with my gearing I could not get my front deraulier to change on the first try. Now that the bike is inside a warmen up it is back to normal. I have never had that happen on a bike and I know this was not the coldest morning I have rode. Maybe it was the 40 minutes it spent on the front of a bus speeding down I-5.