These two guys are good friends and were racing each other all afternoon

Notice who is smiling?

And looking back at his friend?

That's because this guy isn't ready to race. Killed it at the start line after getting a little squirrely with the burn out.

And the smiling guy was frequently seen looking back over his shoulder to mock his slow freind. When in front by a long shot at the finish line, it's customary to look back disparagingly and mock the slow poke.. just a little.