it may just be the spacers.

i have 18mm on the rear (RS Technik) and 20mm spacers on the front (H&R) on my M5 and i have vibration at highway speeds. i just accepted it and keep rolling...

 

The outer diameter of the lip on the spacer should be the same size as the hub and the inside of the spacer should be the same size as the hub, so the ring should fit correctly.

 

i would just live with vibration but this is severe. ill take off the wheels and inspect everything tomorrow. and thats funny umichchris, i'll be running the same setup (20 mm up front 18 mm in the rear). ill let you guys know how it goes.

 

If the outer diameter of the lip, inner bore on the spacer, and hub is not the same size, then that spacer is incorrect for your car and will cause vibrations.

 

how can the out diameter of the lip and the inner diamter be the same? im not understanding. will the ring sit ON the spacer? or simply NEXT, UP AGAINST the spacer? please explain

 

I've got the same problem. I have 20 back and 12 up front. At higher speeds I start getting a vibration. I haven't had the time to re-mount the tires and try out if it was the rings or not, but summer tires are coming on soon so will try it out then. If you do try it out, let us know how it goes.

Good luck!

 

Look at the factory wheel the center bore is just large enough to fit over the hub no larger. This centers the wheel and makes sure the wheel and tire does not spin out of round. This is also why that centering ring is so important. With BMW it is not lug centric (centers the wheel tire combo by the bolts), it is hub centric. the hub centers the the wheel tire combo.

 

Okay so i just got back from checking everything out and i put the ring on the spacer than the wheel on the ring (spacer) no more vibration! thanks Healthservices!! appreciate all the help. now i just need to find a place in CT to install struts and springs for a reasonable price.

 

so ur now going to have one extra set of spacers

 

no that was for my front (20mm), the one i ordered from you are for my rear