First, go to the Options screen and set the Difficulty to Amateur and Trophy Presenter to Male. Return to the Main Screen, then press UP, RIGHT, DOWN, LEFT, UP, RIGHT, DOWN, LEFT. Return to the Options screen by pressing LEFT then X. Next, set Difficulty to Professional and Trophy Presenter to "Rider's Choice". Return once again to the Main Screen and press UP, LEFT, DOWN, RIGHT, UP, LEFT, DOWN, RIGHT. A "Ka-ching!" sound will confirm correct code entry. Enjoy the access to all the tracks!
To enable codes, enter CIRCLE, CIRCLE, CIRCLE, SQUARE, TRIANGLE, TRIANGLE, SQUARE, TRIANGLE at the Title Screen. Then, activate the following cheats by entering the corresponding codes at the Title Screen logo after netering the previous code:
DOWN, CIRCLE, LEFT, L1, LEFT, RIGHT, LEFT, RIGHT
CIRCLE, SQUARE, R2, CIRCLE, TRIANGLE, L2, RIGHT, UP