Best project using wheel spacers.

[Maxalama]

Hi everybody, I am planing of using 8mm spacers in the back and I need some tech advice. Now, my hub center is 57.1mm in diameter, and 16mm in length. In case I use 8mm spacers I still have another 8mm left to center the wheel. I have checked some spacers, and obviously I can not go with the ones that have a lip. The wheels are also hub centric, so I just need flat spacers. What I do not understand is why the spacers have one the center bore edges beveled. Could someone explain ? Thanks.

[JoshDub]

I think what our asking is why sapcers have hub centric rings. It's so the wheel is centered correctly on the hub. The spacer fits onto the hubs ring then the the wheel sits on the spacers ring. Thus allowing for correct balance. So yes, you want
hub centric spacers.

[Maxalama]

Let's define 'hub centric'... To my understanding a hub centric spacer (with or without a lip) is the one whose diameter of the centre bore equals the diameter of the centre hub. The lip is used to center the wheel in case the spacer covers the entire center hub heigth. Am I correct ?

I can understand a spacer having a chamfer which should match the baveled inside center bore of the wheel, but I can not understand why a spacer should have a beveled center bore. Is there any reason ?

[JoshDub]

Well if your spacer has covered the hubs bevel, then the wheel is no longer on the ring. you then have effectively canceled out the benefits of the hub centric ring.

Here is a crud illustration (stay with me, I dont have MS paint)

Here you have your currtent setup (> is the hub, closed end is the lip, the open end is where the hole on the wheel/spacer is.)
>>
^ hub and wheel.
>>>
^ hub spacer and wheel. (what it should be for proper balance and getting perfect center)
>>|
^ what your thinking of doing. You taking the hub centric ring out of the equation when getting spacers that do not have one. You are then mating up the flat surface of the spacer to the flat surface of the wheel.
Now you can do that. You just run the risk of vibrations at speeds. The hub centric ring (for the most part) avoids that.

The spacer having the beveled center bore is an extension of the hubs beveled bore so that the spacer does not cover up and "remove" the hub centric ring.

[Rommulus]

Let's define 'hub centric'... To my understanding a hub centric spacer (with or without a lip) is the one whose diameter of the centre bore equals the diameter of the centre hub. The lip is used to center the wheel in case the spacer covers the entire center hub heigth. Am I correct ?

I can understand a spacer having a chamfer which should match the baveled inside center bore of the wheel, but I can not understand why a spacer should have a beveled center bore. Is there any reason ?

Yes, your understanding of "hub centric" is correct. The spacers with the chamfer leading down to the lips (typically only 8, 10 and maybe 12mm spacers have this) are made specifically for OEM wheels. My 5mm (no lip) spacers have a beveled center bore, but I'm not sure what purpose the bevel serves.

And yes, if you are running a spacer over 5mm thick, you should get the ones WITH a lip. If you are going to run OEM wheels get the kind with the beveled/ chamfered lip. If you are running aftermarket get the kind with a straight lip.

[Rommulus]

Well if your spacer has covered the hubs bevel, then the wheel is no longer on the ring. you then have effectively canceled out the benefits of the hub centric ring.

Here is a crud illustration (stay with me, I dont have MS paint)

Here you have your currtent setup (> is the hub, closed end is the lip, the open end is where the hole on the wheel/spacer is.)
>>
^ hub and wheel.
>>>
^ hub spacer and wheel. (what it should be for proper balance and getting perfect center)
>>|
^ what your thinking of doing. You taking the hub centric ring out of the equation when getting spacers that do not have one. You are then mating up the flat surface of the spacer to the flat surface of the wheel.
Now you can do that. You just run the risk of vibrations at speeds. The hub centric ring (for the most part) avoids that.

The spacer having the beveled center bore is an extension of the hubs beveled bore so that the spacer does not cover up and "remove" the hub centric ring.

Hub centric "rings" are the plastic or aluminum adapters that are used for aftermarket wheels with a larger center bore. What you are referring to is the hub lip (on car) and hub lip extension (lip on the spacers). Just wanting to clarify the terms otherwise this thread is going to get very confusing.

[Maxalama]

Is the spacer's beveled centre bore going against the hub ?

[Maxalama]

Hub centric "rings" are the plastic or aluminum adapters that are used for aftermarket wheels with a larger center bore. What you are referring to is the hub lip (on car) and hub lip extension (lip on the spacers). Just wanting to clarify the terms otherwise this thread is going to get very confusing.

Correct. Like I said: the 8mm spacer WILL NOT cover the entire length of the centre hub, but oly half of it, so I can not use a spacer with a lip. The width of the lip added to the diameter of the center hub will make it bigger then the diameter of the wheel's center bore.
Still not clear why a spacer should have a beveled center bore... The hub on my car is not chamfered, but flat (!)

[Rommulus]

Is the spacer's beveled centre bore going against the hub ?

I'm pretty sure the flat side of the spacer goes against the rotor and the beveled side goes against the wheel.

[JoshDub]

Maybe this picture will help

[Rommulus]

Not sure how that pic helps... What is that a 25mm adapter?

[Maxalama]

Not sure how that pic helps... What is that a 25mm adapter?

You are right: doesn't help... This is a spacer/adapter using lug nuts. Audi is using lug bolts. There are 8mm hub centric spacers without a lip, but - of course - beveled. I am with you: no idea why this bevel, unless used to accomodate some kind of center rings.

[Maxalama]

Yes, your understanding of "hub centric" is correct. The spacers with the chamfer leading down to the lips (typically only 8, 10 and maybe 12mm spacers have this) are made specifically for OEM wheels. My 5mm (no lip) spacers have a beveled center bore, but I'm not sure what purpose the bevel serves.

And yes, if you are running a spacer over 5mm thick, you should get the ones WITH a lip. If you are going to run OEM wheels get the kind with the beveled/ chamfered lip. If you are running aftermarket get the kind with a straight lip.

Got it! In case the aftermarket wheels are hub centric, and have an inside beveled center bore I can not use a spacer with a lip. Correct ?

[Rommulus]

Got it! In case the aftermarket wheels are hub centric, and have an inside beveled center bore I can not use a spacer with a lip. Correct ?

I'm kind of confused about what you are asking. It would help to know what wheels you are planning to run and if you will be using hub centric rings. I understand your concern with the thought of "added thickness" of the spacer lip being too big for the center bore of your wheel, but that is not going to be the case. Hub centric spacers with a lip will maintain the overall outer diameter of 57.1. If you are going to be running aftermarket wheels with hub rings, you will need spacers with either no lip or a straight lip design. Maybe this will help a bit: http://www.purems.com/news/?p=12

[SKIDMRK]

use flat 8mm flat spacers, the correct longer bolts and torque the wheel while it's still in the air. No issues.

[Maxalama]

I'm kind of confused about what you are asking. It would help to know what wheels you are planning to run and if you will be using hub centric rings. I understand your concern with the thought of "added thickness" of the spacer lip being too big for the center bore of your wheel, but that is not going to be the case. Hub centric spacers with a lip will maintain the overall outer diameter of 57.1. If you are going to be running aftermarket wheels with hub rings, you will need spacers with either no lip or a straight lip design. Maybe this will help a bit: http://www.purems.com/news/?p=12

I guess the confusion is based on the fact that I do not know how the spacers with a lip work. My assumption is that the lip is necessary when the spacer covers almost the entire height of the center hub. In this case simulates/replaces the center hub in order to center the wheel. But if the spacer doesn't cover the height of the center hub, and if the wheel is hub centric, by having an extra lip around the center hub makes impossible to fit the wheel. Ok, tell me please where my mistake is.

[Maxalama]

use flat 8mm flat spacers, the correct longer bolts and torque the wheel while it's still in the air. No issues.

I though so... Recap: hub centric flat spacers + hub centric wheels (that's what I've been told by the distributor, mentioning 57.1mm as the center bore) + proper bolts (the right length) should do it, right ?! Now: 'no issues' based on your experience or based on what you think ? Thanks in advance.