I was out and about today.

I turned onto the bike path. I passed an older guy on a really nice Trek. Then I set my sights on this younger guy that looked like he was on a beach cruiser about 100 yards ahead.

I could probably have caught him, but dang if I wasn't cruising 18 to 20 MPH, and not closing the gap an inch.

When I did finally catch him at the light at the end of the path, I noticed that he had a rear hub about a foot in diameter, and it confirmed what I was already suspecting.