MX Unleashed

Unlock cheat options:
Select - "Options" tab in the main menu, after press R or L to cycle
from the "Game Settings" option. Do it until you will see "Cheats" option.
Press B to display a keyboard and type to here the following codes:

Unlock 50cc Class: Type SQUIRRELDOG to "Character Completion" option
Open Up Pro Physics: Type SWAPPIN to "Character Completion" option
Unlock all bonuses: Type CLAPPEDOUT to "Character Completion" option

Bowling: WRECKINGBALL
Expert AI: OBTGOFAST
Unlock All Machines: MINIGAMES
500cc Bikes: BIGDOGS
Freestyle Tracks: BUSTBIG
National Tracks: ECONATION
Supercross Tracks STUPERCROSS