On the menu to change carts different carts are given different numbers. It seems to mean acceleration. Only 3 of these carts have sub categories but this doesn’t matter cause if it DOES mean acceleration then most of these carts have the same acceleration as the gold cart…except the speedrun cart which has acceleration higher than gold but lower than rainbow, once again if it means acceleration. This needs proof but if it gets it there could be a sub category for the speedrun cart…I can’t test it myself right now though cause I don’t have it right now.