265 fit on stock rear rim?

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07-09-10, 11:24 AM

#16

flowrider

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Quote:

Originally Posted by Galaxy 40

Is the width of the wheel also a factor? I tried the tire calculator and did not see an inputs for wheel width. (don't tires stretch on wider rims giving it a lower tire sidewall.Right or wrong?) What If I have a 19x10 for the rear and use a 285/30 won't that have a smaller OD as to a 19x9 on a 285/30? Any formula for this?

Also what would a 285 sidewall look on a 19x10 rim?
Straight?
Slanted?(stretched)
chunky?(due to too much rubber)

Thanks

It is my understanding that wheel (rim) width does not affect the OD of a particular tire. However, it does affect the cross section of that tire. If you look at a tire chart, each tire size has a corresponding wheel width listed. For example, for a 285/30/19, that wheel width is 10". The cross section of that tire will change by .2" for every change of .5" in wheel width from the measured wheel. .2" equals 5mm. So, in my case, using a 285/30/19 tire on a 9" wide rim would decrease the cross section to 275mm from 285mm. Going to a wider wheel would increase the cross section by the same amount, .2" (5mm) for every .5" decrease or increase in width.

Note - Cross section is the widest part of the tire, not the tread width.

Therefore, tires mounted on a wheel that is too wide, stretched, would not change their OD, but, would lose air if they could not make a seal with the wheel's bead.

Lou

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07-09-10, 11:28 AM

#17

Joe Z

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Quote:

Originally Posted by lobuxracer

The speedometer doesn't affect resale. The odometer does. While the 285 is only going to add 0.8 miles per hundred miles traveled initially, as the tire wears down it will be farther off. The OEMs are held to tight standards for odometers, but not speedometers. Honda got badly beat up for inaccurate odometers at one point.

So, regardless of wear, the smaller diameter tire will show higher mileage for the same distance traveled. If resale is important to you, it would be wise to know this before slapping on a set of tires in an alternate size. Again, 2% is considered fair enough and a 285/30 is well within 1%, so it's not unreasonable to run a 285. If you have enough rim, you'd definitely be better off with the 295 for the long run.

Should we even factor in what the Front sizes will do for the ODO or Speedo read outs ???