To race in a fishing boat, unlock all the hidden tracks first. Then, at the Boat Selection screen, highlight Thresher and then hold the L and R buttons and press View twice. Then select Chumdinger and you will race in a fishing boat.
11/17/2000
Extra Track
Before you start a game, head to the Options menu and highlight back. Press up, up, down, up, down, down, start and you will open another secret track!
6/12/2001
Clean Pause
Pause the game and when the game is paused, press the X and Y buttons simultaneously.
7/20/2001
Super Start
To get a jump start on the competition, wait until the announcer starts counting down. Immediately after he says, 'three', press and hold the R-Trigger. Immediately after he says, 'two', let go of R-Trigger and hold L-Trigger. Immediately after he says, 'one', let go of L-Trigger and hold the R-Trigger. When he says, 'Go, go, go!', you will get a nice boost and you'll hear 'Super Start!'
7/20/2001
Boost Jump
After picking up some boost power-ups, you can do a special jump without the help of a ramp. If you hold the L-Trigger (brake) then Press A, you will be boosted into the air. This is great for getting those power-ups that are just out of reach.
4/16/2003
All Boats and Tracks
Enter the following code when you get a high score : ?PB