Axel hole is 6.5mm by 6.5mm. 

Print Settings

Printer:

Ender 3 S1

Layer Height: 

0.2

Infill: 

Cubic @ 20%

Notes:

Printed with 2 Walls

There are three versions. One with 8 spokes, one with 6, and one with 4. These essentially are a suspension of sorts with 8 spokes being able to support a lot of weight, 6 being a middle ground and 4 being a light version.