Wheelies, endos, drive on two wheels, etc.
When on a bike, hold Circle and press the Analog-stick Down to make the bike do a wheelie, while pressing the Analog-stick Forward will make it do an endo (stoppie). Tilting the Analog-stick Left or Right will decrease its turning radius. In cars or trucks you will drive on two wheels. Note: Wheelies and endos will not work on choppers as well as on the sport bikes.