Interesting situation when I left work yesterday. I rolled my bike out of the building (this client has an indoor bike storage area,) hopped on and started for home. Immediately something didn't feel right. I looked down and my rear tire was flat.

So I wheeled the bike back inside so I could at least fix the tire in air conditioning. Pulled the wheel, swapped the tube and replaced the wheel without too much fanfare. This was the first flat I've gotten on this bike (bought it a year ago) so I got to try out the new CO2 inflator I bought at the same time. Worked pretty well, which was a relief. Later when I got home I released all the CO2 and filled the tube with proper air from my pump.

After I put the wheel back on, I noticed the rear derailleur was stuck in the highest gear. Odd. It wasn't like that when I first tried to ride away twenty minutes earlier. Upon inspection I discovered the derailleur cable was completely slack. I have no idea how that happened. So I spent a few minutes setting up the derailleur from scratch. Glad I know how to do my own maintenance, otherwise I'd be calling for a ride home.

I thought about just riding home in high gear and deal with fixing it when I could put the bike on my work stand in the garage. Then I remembered the monster hill upon which I live, and realized there was no way I'm strong enough to pull that high gear up the hill even if I dropped the front into the smaller ring. So I'd be walking that hill for over a mile. In bike shoes. Doing a quick calculation I decided that I could probably fix the derailleur faster than I could walk the hill, so I just dealt with it right then and there.

At first I thought it was a really weird coincidence that I had a flat tire and my derailleur went slack at the exact same time. I was suspecting perhaps someone vandalized my bike? I decided that the "smoking gun" would be testing the tube. If the tube had no holes in it then maybe someone did indeed let the air out of the tire and loosen the clamp on my derailleur. However, when I got home I put the tube underwater and confirmed that there was a pin hole in the tube. I was just being paranoid. It actually was just a weird coincidence that both things happened at the exact same time.