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      11-19-2018, 04:22 AM   #1
Tassadar
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Wider "Stock" Rims?

This may sound like a dumb question: Does BMW make the same stock rims but 1" wider?

Bought car used and found the tires were way wider than stock:

Stock F: 225/45
Stock R: 255/40

Mine F: 245/40
Mine R: 285/35

The rims look exactly like stock rims from the side. What was odd was that the tires actually they sit on the rims perfectly. With 30mm increased width, the tires would budge on the sides of stock rims.

When I finally got around to taking the wheels off and measuring, to my amazement, the rims were 1" wider than stock with the same offsets:

Stock F: 8" ET42
Stock R: 9" ET30

Mine F: 9" ET42
Mine R: 10" ET30

I didn't think they made Rims that looks the exact same as the stock rims but were 1" wider with the same offsets. WTF???

Did BMW actually make wider stock wheels or are these some aftermarket knockoffs?

This is what they look like:
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      11-19-2018, 04:44 AM   #2
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Afaik bmw made style 224 only in 1 widht set (8"front, 9"rear)

Are you SURE you measured the correct way? within the bead seats? (that means taking off the tyres)

If I look at your picture the tyres look pretty puffy on there but its not the best picture to judge. More detailed pics, taken in the line of the rims, (especially from the front wheels) would be better in this case so people can actually see and compare.
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      11-19-2018, 09:47 PM   #3
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Quote:
Originally Posted by GuidoK View Post
Afaik bmw made style 224 only in 1 widht set (8"front, 9"rear)

Are you SURE you measured the correct way? within the bead seats? (that means taking off the tyres)

If I look at your picture the tyres look pretty puffy on there but its not the best picture to judge. More detailed pics, taken in the line of the rims, (especially from the front wheels) would be better in this case so people can actually see and compare.
Hum... You got me there. I was measuring the width on the outside edge, not inside where the bead seats. I can see that accounting for 1/2" on each side making the 1" difference. At least I measured the offset correctly

Man,... I spent so much time trying to find who sells the same rims but 1" wider.... turns out I just measured it wrong

Thanks for the help.... Now i'm worried maybe the 285's on the 9" is a safety concern.
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      11-20-2018, 02:43 AM   #4
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A 285 tire may be different between manufacturers, it depends on the tire side wall design and how they measure.
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      11-29-2018, 11:10 PM   #5
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What’s stamped on the back of the wheels?
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      12-23-2018, 08:56 PM   #6
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Quote:
Originally Posted by Tassadar View Post
Hum... You got me there. I was measuring the width on the outside edge, not inside where the bead seats. I can see that accounting for 1/2" on each side making the 1" difference. At least I measured the offset correctly

Man,... I spent so much time trying to find who sells the same rims but 1" wider.... turns out I just measured it wrong

Thanks for the help.... Now i'm worried maybe the 285's on the 9" is a safety concern.
For most 285s the rim width range is 9.5"-11". You're only 1/2" of pinch so you should be fine. I've been running 275s on 8.5" rims for both AX and track days with no issues.
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      12-25-2018, 03:00 AM   #7
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Quote:
Originally Posted by dc_wright View Post
For most 285s the rim width range is 9.5"-11". You're only 1/2" of pinch so you should be fine. I've been running 275s on 8.5" rims for both AX and track days with no issues.
Physically speaking you can fit that big of a tire, but the tire won't be working they way it's intended to do. There's a reason why race cars run an equal/wider rim compared to the tire width. To stay with the 285 tire, on a race car they would probably use an 11" wide wheel if the rules would allow.

But as I said before, "A 285 tire may be different between manufacturers, it depends on the tire side wall design and how they measure".
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