Center Bore on Aftermarket Wheels made for Audi

freesole · 02-16-2022, 11:56 AM

I have a set of great looking BCForged HCS02 that were made for my Audi SQ5. I was hoping that they would just fit right on the X3M but it turns out that the center bore is a little off on these wheels (Even though they fit my SQ5 perfectly) - so it does not want to sit flush. I was told that I could get a flap disk and expand the center bore on the wheels a bit so that it would fit my X3M.

Has anyone done this before or does anyone have experience here? Contemplating just selling these wheels but I think they would look great on the X3M.

95wildtt · 02-16-2022, 12:29 PM

Hi,

Those are sweet wheels!

From what I see online, the SQ5 has a 66.6 (through 2017) and a 66.5 (2018+) CB. The X3M is also a 66.6, so they should fit.

Assuming you tried to fit them, but they don't sit flush, correct?
Weird.

I've never used anything to enlarge the bore, new to me

freesole · 02-16-2022, 01:48 PM

Quote:

Originally Posted by 95wildtt

Hi,

Those are sweet wheels!

From what I see online, the SQ5 has a 66.6 (through 2017) and a 66.5 (2018+) CB. The X3M is also a 66.6, so they should fit.

Assuming you tried to fit them, but they don't sit flush, correct?
Weird.

I've never used anything to enlarge the bore, new to me

Yeah based on paper, you would think it would fit perfectly but they do not. Tried on both the car by itself and on BMW spec spacers and both did not fit against the wheel. Shoving it in is also not an option lol.

Bmock17 · 02-16-2022, 01:53 PM

Quote:

Originally Posted by freesole

Quote:

Originally Posted by 95wildtt

Hi,

Those are sweet wheels!

From what I see online, the SQ5 has a 66.6 (through 2017) and a 66.5 (2018+) CB. The X3M is also a 66.6, so they should fit.

Assuming you tried to fit them, but they don't sit flush, correct?
Weird.

I've never used anything to enlarge the bore, new to me

Yeah based on paper, you would think it would fit perfectly but they do not. Tried on both the car by itself and on BMW spec spacers and both did not fit against the wheel. Shoving it in is also not an option lol.

I went through this exact same thing back in June. I traded in my b9 SQ5 for my f97. I had a set of BC Forged wheels that I tried to fit on the X3M. Like you, I thought they would fit, but they didn't. I couldn't get them on flush. Bottom line, I couldn't get them to fit. I ended up selling the wheels.

lagunablue1 · 02-16-2022, 02:00 PM

A competent machine shop should be able to evenly bore them out for you if the rest of the wheel specs are a good match for the f97. I've had it done in the past for a set of wheels for a former S2000 of mine.

Just make sure the machine shop you go with is well-rated and you shouldn't have any issues.

spta97 · 02-16-2022, 05:15 PM

Quote:

Originally Posted by lagunablue1

A competent machine shop should be able to evenly bore them out for you if the rest of the wheel specs are a good match for the f97. I've had it done in the past for a set of wheels for a former S2000 of mine.

Just make sure the machine shop you go with is well-rated and you shouldn't have any issues.

Yea I would trust a good machine shop vs. a flap disc.

This is something you really don't want to mess with yourself as it needs to be perfect.

goldfz8 · 02-16-2022, 05:29 PM

you really don't need to do much, you can use sand paper to clean up the hub and center of the wheel. If you had to take off multiple mm machine shop would be the way but you would be fine. I've done it on drag wheels I had before on my 135 with a dremel and took significant material off without issue.

freesole · 02-17-2022, 06:50 PM

I don't think this is a couple of mm's. I think it's honestly a mm or less that is causing it to not sit flush. I still don't trust myself though but would try it if I saw a tutorial somewhere.

95wildtt · 02-17-2022, 07:12 PM

Quote:

Originally Posted by freesole

I don't think this is a couple of mm's. I think it's honestly a mm or less that is causing it to not sit flush. I still don't trust myself though but would try it if I saw a tutorial somewhere.

Just asking, but did you clean off the hub, the face of the hat on the rotor and the inside of the wheel with some steel wool or a wire brush to remove all of the rust and gunk?

r33_RGSport · 02-17-2022, 08:14 PM

The issue that you guys are having is not the center bore.
But the hub lip design.
It has the taper and the amount of tapering is different between BMW and Audi.

I just found out about this too.
My customer with Audi RS5 is using HRE Flowform wheels and added Audi Spacer to push it out more.
He got warped rotor because the wheel couldn't sit flat against the spacer.
It is due to the tapering.

Not sure about BC Forged, maybe the wheels backpad doesn't have the taper, while BMW Hub do have the taper.
In short, it is not the center bore issue.

freesole · 02-17-2022, 10:06 PM

Quote:

Originally Posted by Bmock17

I went through this exact same thing back in June. I traded in my b9 SQ5 for my f97. I had a set of BC Forged wheels that I tried to fit on the X3M. Like you, I thought they would fit, but they didn't. I couldn't get them on flush. Bottom line, I couldn't get them to fit. I ended up selling the wheels.

Yeah, exact same scenario. Didn't realize they would machine it so specific to Audi even if paper specs look the same.

freesole · 02-17-2022, 10:16 PM

Quote:

Originally Posted by r33_RGSport

The issue that you guys are having is not the center bore.
But the hub lip design.
It has the taper and the amount of tapering is different between BMW and Audi.

I just found out about this too.
My customer with Audi RS5 is using HRE Flowform wheels and added Audi Spacer to push it out more.
He got warped rotor because the wheel couldn't sit flat against the spacer.
It is due to the tapering.

Not sure about BC Forged, maybe the wheels backpad doesn't have the taper, while BMW Hub do have the taper.
In short, it is not the center bore issue.

Good points. I guess without any history of a successful refinish, I'm better off selling these wheels.

iBleedOrange · 02-18-2022, 04:36 AM

Quote:

Originally Posted by r33_RGSport

The issue that you guys are having is not the center bore.
But the hub lip design.
It has the taper and the amount of tapering is different between BMW and Audi.

I just found out about this too.
My customer with Audi RS5 is using HRE Flowform wheels and added Audi Spacer to push it out more.
He got warped rotor because the wheel couldn't sit flat against the spacer.
It is due to the tapering.

Not sure about BC Forged, maybe the wheels backpad doesn't have the taper, while BMW Hub do have the taper.
In short, it is not the center bore issue.

Do you know if BBS would have this same issue?

r33_RGSport · 02-18-2022, 08:47 AM

Quote:

Originally Posted by iBleedOrange

Quote:

Originally Posted by r33_RGSport

The issue that you guys are having is not the center bore.
But the hub lip design.
It has the taper and the amount of tapering is different between BMW and Audi.

I just found out about this too.
My customer with Audi RS5 is using HRE Flowform wheels and added Audi Spacer to push it out more.
He got warped rotor because the wheel couldn't sit flat against the spacer.
It is due to the tapering.

Not sure about BC Forged, maybe the wheels backpad doesn't have the taper, while BMW Hub do have the taper.
In short, it is not the center bore issue.

Do you know if BBS would have this same issue?

Not so sure.

spta97 · 02-18-2022, 06:28 PM

Quote:

Originally Posted by iBleedOrange

Do you know if BBS would have this same issue?

I just got a set of BBS CI-R (20") and do not have any fitment issues and they are listed as compatible by BBS.

You do have to use their PFS ("Precision Fitment System") ring for the BMW center bore which is an aluminum centering ring which is held in by a retaining wire/spring and pretty much becomes part of the wheel.

Happy with the fitment and look.

02-16-2022, 11:56 AM	#1
freesole Private First Class 231 Rep 149 Posts Drives: 2022 BMW X3M, 2022 Audi RS6 Join Date: Nov 2014 Location: United States iTrader: (0) Garage List 2022 BMW X3M Compet ... [0.00] 2022 Audi RS6 [10.00]	Center Bore on Aftermarket Wheels made for Audi I have a set of great looking BCForged HCS02 that were made for my Audi SQ5. I was hoping that they would just fit right on the X3M but it turns out that the center bore is a little off on these wheels (Even though they fit my SQ5 perfectly) - so it does not want to sit flush. I was told that I could get a flap disk and expand the center bore on the wheels a bit so that it would fit my X3M. Has anyone done this before or does anyone have experience here? Contemplating just selling these wheels but I think they would look great on the X3M.
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02-16-2022, 12:29 PM	#2
95wildtt Need mo $$s 873 Rep 913 Posts Drives: 2020 X4M Competition Join Date: Oct 2010 Location: Westfield, IN iTrader: (0)	Hi, Those are sweet wheels! From what I see online, the SQ5 has a 66.6 (through 2017) and a 66.5 (2018+) CB. The X3M is also a 66.6, so they should fit. Assuming you tried to fit them, but they don't sit flush, correct? Weird. I've never used anything to enlarge the bore, new to me __________________ 2020 TRM-BLACK X4///M Competition 2020 Porsche Macan 1995 Dodge Stealth TwinTurbo Past: 2020 X3M, 2019 TTS, 2008 X5 4.8 M Sport Last edited by 95wildtt; 02-16-2022 at 01:02 PM..
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02-16-2022, 02:00 PM	#5
lagunablue1 Second Lieutenant 354 Rep 207 Posts Drives: E90 M3 / F97 X3M Join Date: Jun 2020 Location: ON iTrader: (1)	A competent machine shop should be able to evenly bore them out for you if the rest of the wheel specs are a good match for the f97. I've had it done in the past for a set of wheels for a former S2000 of mine. Just make sure the machine shop you go with is well-rated and you shouldn't have any issues. __________________ -2007 Z4M - Interlagos Blue -2008 E90 M3 - Interlagos Blue, 6MT, slicktop -2020 X3MC - Phytonic Blue
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02-16-2022, 05:29 PM	#7
goldfz8 First Lieutenant 381 Rep 372 Posts Drives: 08 Bmw 135 Join Date: Aug 2014 Location: NYC iTrader: (0)	you really don't need to do much, you can use sand paper to clean up the hub and center of the wheel. If you had to take off multiple mm machine shop would be the way but you would be fine. I've done it on drag wheels I had before on my 135 with a dremel and took significant material off without issue.
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02-17-2022, 06:50 PM	#8
freesole Private First Class 231 Rep 149 Posts Drives: 2022 BMW X3M, 2022 Audi RS6 Join Date: Nov 2014 Location: United States iTrader: (0) Garage List 2022 BMW X3M Compet ... [0.00] 2022 Audi RS6 [10.00]	I don't think this is a couple of mm's. I think it's honestly a mm or less that is causing it to not sit flush. I still don't trust myself though but would try it if I saw a tutorial somewhere.
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02-17-2022, 08:14 PM	#10
r33_RGSport General 13109 Rep 18,785 Posts Drives: G09 XM, G05 X5 40, 991.2 T Join Date: Oct 2009 Location: So. Cal iTrader: (6)	The issue that you guys are having is not the center bore. But the hub lip design. It has the taper and the amount of tapering is different between BMW and Audi. I just found out about this too. My customer with Audi RS5 is using HRE Flowform wheels and added Audi Spacer to push it out more. He got warped rotor because the wheel couldn't sit flat against the spacer. It is due to the tapering. Not sure about BC Forged, maybe the wheels backpad doesn't have the taper, while BMW Hub do have the taper. In short, it is not the center bore issue. __________________ Email:sales@rgsport.com \| IG:RGSport_USA \| Web:RGSportShop.com PM for Everyday DEALS!! MSS • iSweep • RaceChip • Sterckenn • AutoTecknic • Akrapovic • Vossen Wheels • Eventuri Active Autowerke • KW • H&R • Ohlins • Remus • and more...
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