Go to options then codes and enter one below.

LOKSMITH- GET CHEAT MODE
POPULATE- GET ALL CHARACTERS
YARDSALE- GET ALL COSTUMES
TRAKMEET- GET ALL TRACKS
WHEELS- GET ALL BIKES
FLYSOLO- NO BIKE
WTCHKPRS- GET SLOW MOTION
ALLFREEK- GET ALWAYS FREEKOUT TIME

*NOTE- The cheats DO NOT work in circut mode
Plus im not sure if the cheats save on your memory card, or you have to enter them in each time you play.

Enjoy!

Daman787