Things You'll Need
Instructions
Unlocking All Characters in Sonic Riders
Unlocking the first four characters in the list above is as easy as beating the game in its entirety. To obtain Dr. Eggman you must complete the Babylon story mode. You unlock Shadow the Hedgehog, Rouge the Bat, and Cream the Rabbit by completing the Hero story mode.
Unlocking E10000-G will come along with beating all of the story modes, or before. You need to log at least 15 hours of game play. Also you can unlock this one if you participate in 100 races.
Obtaining all Gold Medals in the Storm's, Wave's and Jet's missions will unlock the Chaos Emerald Board. Equip the board to Sonic the Hedgehog and he will transform into Super Sonic the Hedgehog. Completing all of the the Storm's, Wave's and Jet's missions will also unlock the characters Aiai, Ulala and Nights. Those characters will become available even if you don't get all gold medals in the races.
Logging 50 hours of game play will earn you the Sonic Rider E10000-R. Hopefully in trying to unlock Aiai, Ulala and Nights you unlock E10000-R.
Unlocking the final character is just a few races away! You must finish first place on these courses: Night Chase, Red Canyon, Ice Factory, White Cave, Dark Desert and Sky Road. Once completed that will unlock the Babylon Story Digital Dimension. Beat that story mode and then you will have unlocked the final character Babylon Guardian.