Tire Size Calculator?

[CinneaghTR]

This post complements quite a few of those concerning new wheels and tires.

Does anyone know how to calculate what size tires will fit on a certain size wheel?

For example, if I have 15 inch diameter, 4.5 inch width wheels, what are my tire size options? I, of course, know the stock size, but I would like to exercise my options.

An online calculator would be great.

TIA.

 

[GB1]

Try this out

https://www.1010tires.com/TireSizeCalculator.asp

Patrick

 

[martx-5]

There's some info here that addresses what you are looking for. Essentially what it says is that for tires with an aspect ratio of greater then 50, the rim width should be at least 70% of the tire width. In other words, a 4 1/2" rim (114.3mm) when divided by .70 equals 163mm...or, the 165 tires that normally go on that size rim. The site explains why going wider is generally not wise. Using those calculations, a 5" rim will allow a 185 size tire. Of course, a wider tire needs to have the aspect ratio drop to retain the original tire diameter if you want the speedo and overall gearing to remain intact.

The link that GB1 gave you should handle those calculations.

 

[CinneaghTR]

Thanks guys!! Much appreciated.

 

[Ab Crevoiserat]

You might want to try this one, I found it easy to use and it has graphics https://www.rims-n-tires.com/rt_specs.jsp;jsessionid=CB6B3ECC7B0BA2CE0D6D2624839A6B50
Wheel / tire size calculator / comparer - RIMS-N-TIRES
good luck

 

[CinneaghTR]

That is an especially helpful calculator, Ab, even though it will not allow a rim width smaller than 5 inches (!).

Thanks to you and the others that responded.