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I just had a weird thought about wheel bolt lengths.

When spacers get bought and sold on here, everyone rightly states they need to use longer wheel bolts equivalent to the thickness of the spacers.

Why is there no recommendations around bolt lengths when different wheels are sold?

Are ALL wheels the same thickness at the bolt holes?

I was thinking about some aftermarket wheels and realised I have no idea whether that part of the wheel is thicker or not and whether I’d need new bolts.

Any wisdom?

I don't really know but I expect BMW wheels would all deliberately have the same thickness to avoid having to stock different length bolts at the factory.

Had a quick realoem lol

Seems to list most models with the same part number. So as mentioned I think it’s a standard size.

kis wrote: ↑Sun Apr 22, 2018 10:38 pm Had a quick realoem lol

Seems to list most models with the same part number. So as mentioned I think it’s a standard size.

What about aftermarket wheels? Do they make any statements regarding their thicknesses or length of bolts required?

Isn't it the thickness at the centre that gives the offset?
Or is it the distance from the centre to the outside edge?

Good question OP.

Anmarube wrote: ↑Mon Apr 23, 2018 6:30 pm Isn't it the thickness at the centre that gives the offset?
Or is it the distance from the centre to the outside edge?

Good question OP.

Offset is the latter. It’s the number of MM difference of the hub face from the wheel centre.

I just realised I could sleep walk into having bolts that are too short when buying a new set of wheels. But then also realised I couldn’t remember reading anyone else doing this. Just seemed weird to me.