1. Easy, any of mine. I buy them because I simply want to ride them, as opposed to riding them simply. No impression intended, other than "that old guy has a clean old bike." When on a Centurion, I'm just hoping someone asks about it, so I can convert a heathen. When on my Cinelli, I'm just hoping no one rides too close and I wipe out.

The only impression I ever try to create is that I'm able to keep up, despite the old bike I'm on. Like most of us, I'm always willing to talk bikes, but I know so very little about modern stuff, I generally just listen. I may ask about the group or the wheelset, or the saddle.

2. As an observer, I'm almost always going to say something, because I want the other rider to know I appreciate their bike. I'll ask questions if I'm curious. Like others here, that often means I have to run the bike down.

Not long ago, I was on my Cinelli/Centurion, riding with a girl on her Cervelo. We chased down a trio of Cervelos, and caught up. We joked about the Cervelo mafia....and then the oldest of the other riders realized I was on a Cinelli, and explained it to the others as "back when bikes were bikes..." We had fun, the younger folk exchanged emails on their smart phones, and I got to pull 4 aero-tucked Cervelos for 17 miles, until we split up.