Originally Posted by trackhub

Well, if you get dog poop on your tires, it's not the worst thing. You know where it came from, you know what it's all about, and you always know where you stand with dog poop.

The worst: Gum on a hot summer day. The pavement gets frylator hot, the gum turns to a liquid state, and Yahhh! You've got it on your tires, getting your day gummed up!!