All Riders
Select Freestyle, Sierra, Time Trial. Set the laps to 6 and turn off all Blades. Then put Edge as Blade 2. Start and pause gameplay, then quit. At the Race Configuration screen, press Triangle. At the Rider Selection screen, press Triangle. Now quickly press Up, Down, L1, R2, R1, L2, Circle, Select. If done correctly, the message "All Riders Enabled" will appear near the lower right corner.