Sure, you can use the Joy-Cons to race, but it's an entirely different experience with racing wheels. These are six of the highest-rated we could find.
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Hori Mario Kart Racing Wheel Pro Mini for Nintendo Switch
I’m going to let the good times roll with Nintendo, because the only thing funner than bombing through Hyrule Motocross is knocking an opponent aside with a shell in Mario Kart. The game is in its eighth iteration, and when it first released on the Switch, Nintendo sold us wheels with a Joy-Con cutout to recreate driving feel. I never liked these because a disembodied wheel turning in midair felt too vague. Hori makes two different wheels for Mario Kart. The Pro Deluxe is a full-size version, while this wheel, the Pro Mini, seems like the better pick for kids. And it comes with one awesome feature the other omits: an item button. With the Pro Mini wheel, mayhem is a big red button press away, and the button just happens to be in the wheel’s center. I wish pressing my real car horn would jettison a blue shell at all those that cut me off.