What is the fastest kart and character configuration in Mario Kart 8?

Solution 1:

I've got a combination that gives 5.75 speed out of 6:

The combination with the fastest top speed is Wario/Bowser/Morton in the Mach 8/Sports Coupe/Circuit Special/Gold Standard with Slick/Cyber Slick tires and any glider. This gives you a speed of 5.75/6

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