Complete Guide to Reading the Sidewall of your Tyre
BEING ABLE TO READ A TYRE SIDEWALL SAVES LIVES!
Well maybe that's an exaggeration, but being able to correctly interpret the sidewall of the tyre will save time for both you and your tyre fitter when it comes to getting a quote. So in this guide we're going to show you how to read the sidewall and what each of the symbols mean.
When reading a sidewall in preparation for a tyre change. The important information needed for a quote is the tyre size, construction and rim size:
Here's an example Tyre Size: 195/55 R16
195 = Tyre Width
First we need to look at the width of the tyre - from sidewall to sidewall. The "195" is the width of the tyre in millimetres.
55 = Tyre Aspect Ratio
The aspect ratio is used to work out the height of the tyre. In this example the aspect ratio is "55", so the height of the tyre is 55% of the width (195 x 55% = 107).
R = Construction
The construction of the tyre is marked by a letter as opposed to a number. The letter in our example "R" denotes a radial construction, which is the most frequently used tyre in the UK.
You may also see other examples such as "B" for Bias-ply or "D" for Diagonal construction.
16 = Rim Diameter
After the construction letter, the numbers represent the rim diameter. Our example shows a "16" inch wheel rim.
Other Important Markings
Load Index - If you carry additional load over and above normal everyday use. Then it is important to take note of the load index when asking for a quote. For example a load index of 87 is capable of supporting up to 545kg.
Speed Rating - Represented in letters from A to Z. Each letter signifies a maximum speed which the tyre is able to operate under. For example a speed rating of V is capable of supporting a speed up to 149mph. Although tyres can operate at much higher speeds, this does not mean you should brake the legal limit.