Spacer question, bolt on Vs bolt through

[StratosFearXX]

Why do some wheel spacers bolt to the hub then the wheel bolts to the spacer, and others the wheel bolts to the hub through the pacer?

 

[DXX]

Because thinner spacers don’t have enough depth for the wheel bolt thread

 

[StratosFearXX]

Because thinner spacers don’t have enough depth for the wheel bolt thread

Well yeah not the skinny ones of course but the 25mm plus ones. I'm looking on PCD Parts and they're available in both types. Wondering if one is better than the other?

Shorter bolts (but with double the number) have better shear strength or something perhaps?

 

[DXX]

Well yeah not the skinny ones of course but the 25mm plus ones. I'm looking on PCD Parts and they're available in both types. Wondering if one is better than the other?

Shorter bolts (but with double the number) have better shear strength or something perhaps?

Bolt through are bound to be cheaper to manufacture as no Helicoils.
Bolt through allows all bolt torques to be checked without removing the wheel.
Two interfaces clamped by one bolt does potentially create more risk of bolts loosening IMO.
‘Double the number’, there are only 5 bolts into the hub and that’s what counts.

 

[andymcvw1]

I used bolt through ones with supplied bolts. I actually just refitted them yesterday