Basically, it speed the player up and ruins the players turning, I don't know how to fix it but it completely ruins a lot of things.
https://gyazo.com/cb2870713290283bab63bdf49828083d
That's an example of what I am talking about.
Set the other characters' parts to massless. The thing that is ruining the turning and player speed is angular momentum, this is built in to the roblox engine. Disabling the mass will bypass this since nothing can have angular momentum without mass.