Hold R1 + R2 + L1 + L2 to take a dive off your bike.
Verified by: this cheat is unverified
Submitted by: swiftshark
on December 23, 2002
To unlock everything in the game press L1 + Left, R1 + Up, L1 + Left, Right, L2 + Triangle, Triangle, R1 + Right, L1 + Right, R1 + Down, R1 + Triangle at the main menu.