[mike sevel]

ECS has some good prices on Alzor wheels. I don't understand what the hub centric rings are exactly. Are they like the old-fashioned hub caps that snap on to the rim perimeters? Or are they set in place before the tires are inflated? Are they reliable or a maintenance nuisance?
Thanx,
Mikey

[Welcome to NBA Jam]

They're just plastic rings that center the wheel properly on the hub, otherwise you might get vibrations if you don't perfectly center it with the lugs. You place them in the bore of the wheel. No maintenance needed, but if you swap wheels often then you should get aluminum ones to reduce wear.

[rbryantaz]

Originally Posted by Welcome to NBA Jam

They're just plastic rings that center the wheel properly on the hub, otherwise you might get vibrations if you don't perfectly center it with the lugs. You place them in the bore of the wheel. No maintenance needed, but if you swap wheels often then you should get aluminum ones to reduce wear.

On a BMW with lug bolts the hub centric wheel is more important than most cars because there is no stud to slide the wheel onto so they become more worth it than other cars that have lug studs and nuts. You could also add a hub stud kit and use lugnuts then the centering rings are a lot less critical. I did this on my e46 and I liked it better than the lug bolts.

IMO if you install the lugs and make sure they are slowly tightened in a star and you look to see that they are centered the ring really doesn't do anything. It is really for initial alignment which helps a lot in fast wheel changes (any racing wheel change) and makes it hard to mess up the install for novices or people that are being lazy (anyone can fall into that category from time to time).

With that said, they are cheap so it is worth just getting them. At the same time it isn't a big deal even without them if you are careful, they don't really hold the wheel in place after the lugs are torqued or anything like that.

Plastic rings can also melt on track days if driven hard and the hubs heat up so that is another plus for the aluminum ones.

One tip is that you can coat the rings with RTV between the rim and the ring so they stay installed. I did this for my e70 spare tire setup on my e90. That way the ring is basically part of the rim but can be removed if need be.

One thing to note, never try to enlarge a wheel center with a hand tool if you get a wheel that has a smaller center than your car. The hub center has to be true in order to balance tires. I had to take some 7series wheels to a machine shop to get them enlarged for my e70 when I added the bigger tires...

-Rich