Decrypting The Tyre Sidewall
When we go to buy tyres, there are people who seldom look at the marking on the tyre sidewall, of the tyre they are buying. They usually relay on the feedback of their peers or whatever the shopkeeper is recommending. Your car’s tyre sidewall can help you there. Those markings can actually help us a lot in understanding the tyres themselves, and also if they suit our requirements or not.
Here we will take 15” Euro Star Series tyre manufactured by General Tyre and Rubber Company since it is an OEM tyre for both Toyota Corolla variants and Honda Civic, in Pakistan, and will decode all those lettering and number that you see on the tyre sidewall and see what they actually mean. Many of our readers are auto enthusiasts and they might already know what they mean. But many are new in this circle of ours, or are just trying to learn new things about the cars they drive. So this article is for them.
One major line of digits and lettering you will always notice on tyre sidewall is something like this:
195 65 R 15 91H
Let’s break it down and examine them.
- 195 It is the width if the tyre in millimeters.
- 65 It is the aspect ratio; meaning, it is 65% of the width of the tyre, that was 195 mm. Simply put, 65% of 195 mm.
- R stands for “Radial”.
- 15 is the diameter of the wheel in inches. This tyre will fit on a 15 inch alloy wheel.
- 91 is load index. It means how much load each tyre can bear. 91 load index means tyre can carry 615 kg of weight on it. And ‘H’ stands for the speed rating. Higher the alphabet, higher the speed rating. A tyre marking symbol of ‘H’ is safe to the speed of 210 km/h.
On imported tyres, you can also find the week and year of manufacturing of the tyre. Look for 4 digits stamped on the sidewall near the bead of the tyre. It could be something like this, “1411”, like in the photo at the right. The first two digits represent the week and last two are the year of manufacturing. So you can say that the tyre was made in the 14th week of year 2011.
One can also find a lot of other information on the sidewall of their car tyres; like their ply construction, maximum load and inflation limits, traction rating, tread-ware rating and operating temperature ratings, etc. You will find batch numbering on the tyre sidewall as well. Those are usually for internal use of the company.