E

Extreme G

Extreme Speed - Enter 'xtreme' as your name at the name selection screen (Contest Mode)

Easy Win - Enter your name as 'RA50' and no matter if you quit in the middle of a game, you will still be registered as the winner.

Ultimate Password - Enter 81GGD5 at the password screen to unlock all the hidden bikes and the special.

Stealth Mode - Enter 'stealth' at the name entry screen and all the drivers will be invisible.