This is so funny. Man, I totally yell out "WHOO HOO" occasionally when I ride. The funner the trail, the more I hoot. I even sing. A regular chant of mine is to sing the "Rollercoaster" song by Red Hot Chili Peppers. "Rollercoaster! Whoop! Yeah!." Don't ask me why. Other times, right when I start the ride, I yell "I'm riding! I'm riding!," or "We're riding! We're riding!" It's the sheer joy.