At about 20 miles into 50 mile ride today I am aware of a creaking sound with each pedal stroke coming from what I think is the bottom bracket. It's a carbon frame and cranks, so I figure it's just the frame amplifying whatever it is, and make a note to check it out after my ride.

Then I get a little lost 5 miles later, and stop at the only garage I've seen for a long time to ask for directions. While I'm there I take a look and find that my left crank is coming loose. Yikes! I don't have a wrench large enough to deal with it. I ask the mechanic if he had a wrench I could borrow for 30 seconds. He was really nice about it, and loaned me his wrench set. I tightened it about 1 1/2 turns, got my directions, thanked him kindly and was on my way.

But, wow, that could have ended so much worse. Today I got lucky.