Print for each scooter :-
Shoe x 2 (with support and course layer height)
Bushes x 4 (Suggest high infill for strength)
If you need to scale the model to suit your print bed or scooter, then Use the openSCAD file Bush.scad to generate yourself a custom bush.
Replace the front and rear scooter wheels with these shoes.
Be warned, these are large prints (230mm) at full size.