To enter a cheat below, goto the "Select Event" menu and press C-Up:

Big Bikes:

B1GB1K3S

Big Riders:

G14NTS

Crashes Off:

N0CR4SH

Zero Riders:

N0R1D3RS

More Cameras:

M0R3C4MS

Flying Mud:

B1GSPR4Y

Mercury Gravity:

M3RCVRY

Moon Gravity:

M00N

Venus Gravity:

V3NVS

Saturn Gravity:

S4TVRN

Uranus Gravity:

VR4NVS

Pluto Gravity:

PLVT0

Neptune Gravity:

N3PTVN3

Mars Gravity:

M4RS

Jupiter Gravity:

JVP1T3R