# Importance of centre bore in hubcentric wheel mount design?

I'm hopeing to settle an argument here. I am of the understanding that the diameter of the centrebore is integral to safety in hubcentric wheel mount design.

Does anyone have any well evidenced arguments for or against this standpoint with details of the mathematics involved?

• Don't have the maths, but think of the steel wheels held with concentric cone nuts - they are what locate the wheel centrally . Many alloy wheels have the centrebore holding the wheel central as the nuts have a larger hole tolerance with big flat faces to spread the load on the alloy wheel. Especially obvious with my steel wheels for winter and alloys for summer where I have two sets of nuts.... Jul 10, 2017 at 11:17

Not quite sure what mathematics you are looking for.

The center bore is meant to fit over the hub pilot simply to align the wheel to the hub. Once the lug nuts are in place and torqued properly, the hub pilot has done its job.

On wheels with larger center bores that the hub pilot, a centering ring is used to ensure the wheel is centered. Wheels can be safely mounted without a ring as long as the wheel is centered on the hub.

You could say it is important for safety because if the wheel is not centered, there will be an unbalanced situation that can cause vibration, or worse. But not critical for bearing the load of the vehicle.

Sources -

How is the load handled between a car and its wheel?

The Skinny on Hub Centric Rings