Sonic Riders is based around characters racing each other using devices known as "Extreme Gear", anti-gravity-equipped vehicles consisting of hover boards, hover skates, and hover bikes.[1] Players compete to finish three laps around a racetrack before their opponents and complete the race in first place. Each race features up to eight characters competing. A key component of gameplay is the air tank, displayed in the lower right-hand corner of the screen. Air serves as the fuel for Extreme Gear, and is depleted gradually as the race goes on.[2][3] Characters can also perform a Boost, which will give them a sudden burst of speed at the cost of a significant amount of air. If a player boosts into an opponent, their character will attack and stun the opponent for a brief period. Air is also more quickly spent using techniques like drifting, which allows the player to round sharp turns with ease, and building tension before a jump, which involves using the air to propel the player higher off the edge of ramps.[3] If a player runs out of air, their character will start running on foot; this prevents them from boosting, attacking, cornering easily or using charged jumps. Players can refill their air by using pit stops on the track, which force them to stay in place while their air meter recharges, or performing tricks when jumping off ramps or off an opponents' slipstream, with higher-rated trick sequences restoring more air. Players can also collect rings scattered across the track; collecting a certain number of rings will cause their character to level up for the remainder of the race, increasing the strength of their abilities and extending their maximum air capacity.
Sonic Riders features 16 playable characters,[2][4] nine of which must be unlocked, including guest characters from Nights into Dreams, Space Channel 5, and Super Monkey Ball. Each individual character has different statistics, altering their performance slightly in races, though some characters are restricted from using certain types of Extreme Gear. Characters are divided into three classes, each with different abilities: Speed characters can grind on rails, Power characters can break certain objects, and Fly characters can fly through boost rings.[4] Each race track features multiple shortcuts that can only be accessed by characters of a specific class. Players can spend the rings they acquire at the in-game shop to purchase new Extreme Gear, each of which possesses unique statistics and properties. The game includes eight unique areas, each with two track variants, for a total of 16 tracks. Only five tracks are accessible from the start; the remainder are unlocked through progression in the game's story mode and by winning Gold in both the World Grand Prix tournaments, in which players race through five consecutive tracks and attempt to get the highest overall score.