In options menu, go to cheat codes.
Cheat Effect
getheadj Yellow smile
allin Unlock Special Zone
dfens Unlock Special Agro
getheadm Snowman head
getheadn Skull head
getheadk Pumpkin heads
getheadl Bunny ears
ontheroad Vechicles take no damage
roadtrip Unlocks Atlanta & Detroit
crosscountry unlock all citys in arcade mode
fillmeup Max Nitro
trythisathome If you typed it in correctly, your bikers head should be on fire. NOTE: This only works for Choppers and Streetbikes.