Press and hold L + R + B + Start and power on the system to delete the current saved data.
Get the gold cup in all races to unlock the Special Cup circuit.
Collect 100 coins or more by the end of the cup to unlock extra tracks. Push L or R to view and play them.
Get an A rank on every cup on every class you will unlock all of the original courses from Super Mario Kart.
Finish all circuits in all classes to change the background color of the title screen.
Push L to shoot a green shell or Push R to jump at the character selection screen.
Finish every circuit in any cup in first place and get 100 coins (25 coins per circuit).
Push Select during game play to use the horn.
Push Gas just before the last number turns green during the pre-race countdown.
Immediately before the race starts, when the little turtle cloud appears, hold Gas. When the race starts, you will peel out or smoke your tires then take off.
Push A + B then turn left or right.
Master the power slide technique and use tight turns to your advantage. As you go into a hairpin, press and hold R to jump, then slide. As you straighten out, release R. If timed correctly, you will get a boost of speed.
If you hit a banana peel, immediately brake while accelerating to prevent spinning out. If done correctly, a musical note will appear over your head. Note: This works with a variety of obstacles, such as rocks, puddles, ice, etc.