Get ATC
Come first in eight arcade mode races.

Get Dimension and Viper
Finish ATV Academy Training, and also Trick Training.

Various Cheats
Enter the following names for your profile name to get the desired cheats:

Code - Granted wish

REDROOSTER - Get Champs
DOUBLEBARREL - Get Challenges
ROADKILL - Get All Tracks
BUBBA - Get all riders
GENERALLEE - Get all ATV's
FIDDLERSELBOW - Get all Tricks
GINGHAM - Max out Stats

Quick Turn
When going fast and are trying to turn, use the speed boost while turning. The bike will seem to jump forward.

Backflip Without Going Off Jump
Do a wheelie. Preload while doing the wheelie and release Powerup. You will do a backflip without going off a jump.

Drive into wall
In multi-player freestyle unlimited mode, drive up on ramp that says AC racing upper slanted wall with red stripes. Drive right until you see the vent on floor that is lit. Do a stoppie (press Analog-stick Up + B) and slide into the vent. If done correctly, you will crash and be reset facing the wall. Press A and drive forward slowly. You will see purple and your ATV will become small. You can do tricks and rack up points, but you cannot exit and keep them. To escape, stay upside down until you fall. Do not press L or the game will freeze.