Seicross 





Continue

At the Game Over screen hold A and press Start to continue.





Change the difficulty and change the starting stage

At the Title Screen, on Controller 2 hold Left, A, and B. On Controller 
1 press A to change the difficulty and B to change the starting stage.





Invincibility

At the title Screen, on Controller 2 hold Left, A, and B. On Controller 
1 press Up, Up, Down, Down, Start for invincibility.





Invisible bike

On the Title Screen, hold down A, B, and Left on Controller 1, for an 
invisible bike.