I thought some people might find this useful!

 

A quick guide on how to max each stat in MK8D, without giving a thought to any other stats. Where stats are tied, only one example is given. Be warned; stats max out at 5.75 total, which many of these builds exceed with no benefit:

(Character, Kart, Wheels, Glider)

Max Ground Speed: Bowser, Circuit Special, Slick, Super Glider

Max Water Speed: Bowser, Bone Rattler, Off-Road, Super Glider

Max Air Speed: Bowser, Mach 8, Sponge, Super Glider

Max Anti-Grav Speed: Bowser, Mach 8, Slim, Cloud Glider

Max Acceleration: Isabelle, Mr. Scooty, Roller, MKTV Parafoil

Max Weight: Bowser, Steel Diver, Monster, Wario Wing

Max Ground Handling: Baby Daisy, Pipe Frame, Roller, Super Glider

Max Water Handling: Baby Daisy, Steel Diver, Roller, Wario Wing

Max Air Handling: Baby Daisy, City Tripper, Wood, Cloud Glider

Max Anti-Grav Handling: Baby Daisy, Biddybuggy, Roller, Super Glider

Max Traction/Grip: Bowser jr., Tanooki Kart, Monster, Super Glider

Max Mini-Turbo: Baby Daisy, Biddybuggy, Roller, Cloud Glider

Source: https://www.reddit.com/r/NintendoSwitch/comments/6bvqdj/a_quick_n_dirty_guide_to_max_stats_in_mk8d/