Expert tire people in here please

Afterimage

Afterimage

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This isn't exactly Corvette related as the tire sizes mentioned don't fit a Vette but need a question answered.

A 235/50/17 tire can be mounted on a recommended wheel width range of 6.5-8.5"
A 225/40/17 tire can be mounted on a recommended wheel width range of 7.5-9"

My question is about the max wheel width size, basically if a 225/40/17 tire (narrower and less sidewall) can be mounted on a 9" wide wheel why is the 235/50/17 tire only recommended to be mounted on an 8.5" wide wheel?

Tony
 
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Afterimage said:
So there are no expert tire people here I see only members that know tires are round and black with a hole in the middle....................
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Yes. LOL.
I'm pretty sure any tire store can answer that question. At least they did when I wanted the thinnest winter tire for my rims
 
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Afterimage said:
A 235/50/17 tire can be mounted on a recommended wheel width range of 6.5-8.5"
A 225/40/17 tire can be mounted on a recommended wheel width range of 7.5-9"
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I am not an expert but to my knowledge the 1st number is the width of the tire. It looks to me that the wheel width range on the example you gave is reversed.
 
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Afterimage said:
No it's not reversed, those tire sizes show the wheel width range that is recommended for those tires to be mounted on.
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Why would a thinner tire go on a wider rim ?
235 tire 6.5-8.5"
225 tire 7.5-9"
 
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I picked a tire in that 225/40/17 size and 235/50/17:

Basically I would like to mount the 235 size tire on a 9" wheel which is why I'm wondering why all tire manufacturers say max is 8.5" wheel on that size tire. I don't think it's a big deal personally, if we are talking Vette tire sizing a 325/30/19 (rear tire size on C6 Z06, GS) is recommended on a 12" wide max wheel but Apex has no issue mounting it on their 12.5" wheel. I've even done it when I had my Forgeline wheels (325/30/19 PS4S) on a 19x12.5" wheel and didn't have a problem at all.
 

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Afterimage said:
I picked a tire in that 225/40/17 size and 235/50/17:

Basically I would like to mount the 235 size tire on a 9" wheel which is why I'm wondering why all tire manufacturers say max is 8.5" wheel on that size tire. I don't think it's a big deal personally, if we are talking Vette tire sizing a 325/30/19 (rear tire size on C6 Z06, GS) is recommended on a 12" wide max wheel but Apex has no issue mounting it on their 12.5" wheel. I've even done it when I had my Forgeline wheels (325/30/19 PS4S) on a 19x12.5" wheel and didn't have a problem at all.
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OK, they are different tires. That certainly can make a difference. A tire width is not 100% accurate it all depends on the profile of that particular tire.
The tread width on 2 tires can be the same, but the bead width can be different depending on the sidewall construction making it suitable for different wheel widths.
 
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All 235/50/17 size tires show the same width range, as are the 225/40/17 size (feel free to check any brand of tire that is available in both those sizes). I did not make a mistake in my postings.

It's obvious people here don't know the answer, I'll email a tire manufacturer and see what they say.
 
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Afterimage said:
All 235/50/17 size tires show the same width range, as are the 225/40/17 size (feel free to check any brand of tire that is available in both those sizes). I did not make a mistake in my postings.

It's obvious people here don't know the answer, I'll email a tire manufacturer and see what they say.
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Sorry, I missed the 40/50 profile. LOL. I thought they were both 50's. Sorry about that. I still suggest you contact a tire store. Tirerack is always eager to answer any questions.
But the answer I'm sure is the sidewall stiffness and construction.
 
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True on your first sentence (depending on tire width sizing), on the second if you are talking diameter the wheel is not larger (17" size on both).

Remember the sidewall on the 225/40 will be shorter (40% of 225mm = 90mm (height of sidewall)), 50% of 235mm = 117.50mm.

So you are able to mount a 225/40/17 tire on a 9" wide wheel but why can you only mount a 235/50/17 to an 8.5" wheel? In my eyes you have more sidewall (slightly more flex) so basically it should be easier and able to be mounted to a 9" wide wheel and give the tire a tad better support.
 
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Afterimage said:
True on your first sentence (depending on tire width sizing), on the second if you are talking diameter the wheel is not larger (17" size on both).

Remember the sidewall on the 225/40 will be shorter (40% of 225mm = 90mm (height of sidewall)), 50% of 235mm = 117.50mm.

So you are able to mount a 225/40/17 tire on a 9" wide wheel but why can you only mount a 235/50/17 to an 8.5" wheel? In my eyes you have more sidewall (slightly more flex) so basically it should be easier and able to be mounted to a 9" wide wheel and give the tire a tad better support.
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I think it's the opposite. Being more flexible makes it more likely to break the bead. A stiffer sidewall will not flex as much during hard corners.
 
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