Lawyer lips saved my teeth this week when I rode my disk-brake equipped bike several miles (including several hard stops) with a loose QR skewer. Not sure why it loosened on me--I know how to tighten them properly, and it's been several weeks since I've had the wheel off for any reason.

My first clue that something was wrong should have been the fact that the QR lever was rotated about 90 degrees from its usual position (I generally orient it next to the fork, but figured I must have just been in a hurry the last time I put the wheel on).

My second clue should have been the non-functional speedometer, and the fact that when I checked the magnet-sensor alignment, the magnet had rotated around the spoke--as if it had hit the sensor due to, oh say, a loose wheel flopping around.

My third clue, which was finally sufficient, was the flopping of the wheel I noticed when I did further tweaking of the speedometer sensor position, after still failing to pick up the signal from the magnet.

Today, I certainly have a much prettier smile than I deserve.