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stretching is also used to stiffen the sidewalls on cheap tyres. drifting = many dead tyres and hence people tend to look at cheaper tyres.

just because you dont do it daoesn't mean it's only wank factor

Rubbish. Stretching doesn't stiffen sidewalls. It detracts from roadholding which enables drifters to loose grip (slide) with less power.

Wah?

That's a lot of stretching.

Unless something is wrong here:

9 in = 228.6 millimetres

so 225's on a 9in would give approx 3.6mm of stretch.

AKA nothing noticeable.

The tread of the tyre is roughly the same of width of the rim, so the sidewalls will be more or less right angled.

9.5 in = 241.3 millimetres

235's on a 9.5 would give 6.3mm stretch, which i believe would just start to get noticeable.

If i've got it wrong let me know.

Go look at a 235/45x17 on an 8" wide rim, and tell me if you think a 225 on a 9" would or wouldn't look stretched.

The advertised width of a tyre (225, 235 etc) is not an exact dimension that you can take to the bank. It's nominal, and in fact it changes depending on what width rim you stick it on.

Unless something is wrong here:

9 in = 228.6 millimetres

so 225's on a 9in would give approx 3.6mm of stretch.

AKA nothing noticeable.

The tread of the tyre is roughly the same of width of the rim, so the sidewalls will be more or less right angled.

9.5 in = 241.3 millimetres

235's on a 9.5 would give 6.3mm stretch, which i believe would just start to get noticeable.

If i've got it wrong let me know.

See attached photo. Tyre on the left is a 255 R comp. Tyre on the right is a 235 road tyre. Reckon there is 20mm difference????

For what it is worth the 235 looks underdone on a 9" tyre.

post-5134-0-65521900-1328487952_thumb.jpg

Unless something is wrong here:

9 in = 228.6 millimetres

so 225's on a 9in would give approx 3.6mm of stretch.

AKA nothing noticeable.

The tread of the tyre is roughly the same of width of the rim, so the sidewalls will be more or less right angled.

9.5 in = 241.3 millimetres

235's on a 9.5 would give 6.3mm stretch, which i believe would just start to get noticeable.

If i've got it wrong let me know.

Like said above, seems to work on paper, but not the way it works.

Can provide photos of a 235/45 on a 9.5, doesn't even sit on the wheel. The lip on both side stick out.

9" doesn't include the lip. It's the inner part of the rim i.e. the amount of tread on the ground.

255mm includes the lip, sidewall construction + the usable tread

why do you want to fit an incorrect tyre size on a given rim? years/months/weeks of engineering had gone into it and people fk it all up by mixing and matching the tyre size.

9" doesn't include the lip. It's the inner part of the rim i.e. the amount of tread on the ground.

255mm includes the lip, sidewall construction + the usable tread

why do you want to fit an incorrect tyre size on a given rim? years/months/weeks of engineering had gone into it and people fk it all up by mixing and matching the tyre size.

225 on a 10" wide rim.

no issues here

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