Turbo Start
Hold down A when the race starts for a turbo start.

Get Scooters
At the main menu press C-Down, C-Right, C-Up, C-Left, Z, Z, L, C-Left.

Insanity Level
At Thrash Mode press C-Up, C-Left, C-Left, C-Right, L, R, C-Down, Z.

Be The Cop
Message: Z, C-Left, C-Down, C-Left, Z, L, R, C-Down.

Insanely Fast Bikes
At the main screen put in Up, C-Left, C-Left, C-Right, Left button, Right button, C-Down, and Z.

Stages
Stage 2:
At the main menu, press R, C-Right, Z, R, L, C-Up, C-Left, C-Up.

Stage 3:
At the main menu, press R, C-Right, C-Right, C-Right, R, C-Left, C-Down, Z.

Stage 4:
At the main menu, press R, C-Right, C-Down, C-Left, C-Right, C-Right, Z, L.

Stage 5:
At the main menu, press Z, C-Right, C-Down, C-Left, C-Right, C-Right, Z, L.

Extra Bikes
Use Big Game Mode to finish all the races to get 2 new bikes capable of 300mph+

The Mystery Level
Get at least 52 batteries and assault a cop 19 times in the insanity level,stage 2. You'll hear a chime at main menu press c-up c-down(2x) z z R L L c-down c-right FAST. You won't hear a chime this time go to level 5 get 52 batteries in stage 5 and you'll get the code. Its tricky but you'll get it after the first 10 times, don't lose patience.