hub centering rings: plastic vs. aluminum?

I have tried using no centering rings and so far the results are perfect. Your lug nuts should hold the wheel true.

Chas Hurst

They don't bear any weight at all. All they do is help center the wheel until you can get the lugnuts on, and plastic works fine for this trivial task. The lugs carry 100% of the weight. You can leave the hubcentric rings out with no ill effect. Just observe the normal lug tightening sequence: run them all up finger tight, then torque them in two steps, in a diagonal pattern.

If so, there's a _lot_ of misinformation being spread by people (including wheel manufacturers and car mags). According to Ronal USA's web site:

"A hubcentric fitment, is one where the interior of the backside of the wheel - referred to as "centerbore"-is an exact fit to the "hub"-that protrudes from the mounting surface of the wheel. The relevant issue here is that the WEIGHT BEARING of the wheel on the car is done on the HUB when it is "mated" to the wheel! This has to be an exact fit. The LUG NUTS, simply affix the wheel and hold the wheel to the car and do not affect load bearing."

According to Sport Compact Car magazine:

"Hubcentric wheels have a hole at their center that fits closely over a round feature on the hub, serving to center the wheel on the axis of the spindle, as well as bear the vertical weight of the vehicle. The wheel bolts or studs then serve simply to hold the wheel onto the hub, and are loaded only in tension, where they are strong. If the studs were required to absorb vertical forces, they would be loaded in single shear, the weakest arrangement for any fastener."

I think you're quite probably correct, but there sure is a lot of misinformation out there...

A set of rings is only 10-15 USD, and it seems like good insurance.

I spent the money not spent on hub rings on a bottle of wine. What would hub rings insure?

Chas Hurst

Grant is correct !!!

I have an old set of "PRIME" wheels ams the centers are about VW size. I has always fighting an "out of round" problem with them. Prime did not make "hubcentrics" for them, so I had a set made to match Miata, The out of round problem is gone ! Plastic or Alum. ???? , just get them and use them. They will locate the wheel properly as you put the nuts on.

Bruce RED '91

That the wheels are centered with respect to the hubs. I don't like to rely on humans being able to follow instructions (e.g. lug nut tightening procedure).

You trust a company that sells wheels adorned by Teddy bears??

Another known source of advertiser-driven misinformation.

Removing the wheels again seems like a waste of time. If it ain't broke...

In 40 years of owning cars, my current Rota wheels are the first with hubcentric rings. Not a single one of the others ever fell off. The industry has created a market for yet another unnecessary product.

The most useful purpose served by the rings is keeping small animals from nesting in the gap between hub and wheel. :-)

Personally? No; I believe you're right. I was just pointing out the abundance of mis-information (even from people who _ought_ to know).

I always thought those teddy-bear were just a gag, then I saw a picture on a personal web-page of somebody's car with the teddy-bear wheels.

Apparently. :)

I swap wheels three or four times a year (sometimes in rather a hurry) and I prefer to minimize the sources of error. IOW, I don't trust myself to tighten the lug-nuts in the proper order.

Even with hubcentric rings, you need to torque the lugs properly to prevent a warped brake rotor and ensure that the wheel is seated firmly on the hub.

It's easy, Grant:

1. Finger tighten all four nuts.

1. With a wrench, tighten one nut just past firm, then the one across from it. Then do the other two, in any order you choose.

2. Repeat at 80 ft-lb.

Note: this will be on your final. :-)

But, uh, I was told there'd be no math...

By whom, may I ask? As long as *I* am on this newsgroup, there

Leon

Reading this, I have to think Lanny's assesment is on the dot. We are going to put the weight of the car on soft, fatigue sensitive, aluminum or plastic? Seems more ridiculous than Teddy Bears as wheels.

I have had trouble before with ridiculous claims originating from SCC in this group. I forgot the exact issue, but they still have zero respect in my book.

This is another example of plain stupidity. Fasteners, like bolts and rivets in aircraft skins, are *very good* in supporting "vertical" (sideways) forces. As long as they are tightening down sheared parts that prevent bending moments on the bolts. And the friction between the parts helps too. While I would assume nowadays all modern planes are glued together, in the old days the skin panels were *riveted together*. (I did various labs manufacturing them and computing their strength as an undergrad.) The skin panels are in tension (sideways force.) And no, the aerospace industry does not deal with ineffective components. (Always excepting Air Force 1, of course.)

I think you are right on. And somehow, it always seem to be the same originators.

Leon

Recognizing the number "80" on a torque wrench isn't math--it's Reading Comprehension. The only way to get out of R.C. is to be a mathemetician, or an engineer.

If you mean counting up to four (the number of lugnuts), just use your fingers and you'll do fine.

:-)

In case your torque wrench does not have the number "80" on it, use linear interpolation.

Ah. That explains why I don't comprehend that word.

Ah, advanced digital mathematics.

Leon

Reading

mathemetician,

This is where Grant gets into trouble!

Reading

mathemetician,

This is where Grant gets in trouble!