205/40 R17 Tyres Explained

205/40 R17 is a common tyre size for drivers who want sharper handling and a lower sidewall feel. It suits many passenger cars that favour responsive steering. The dimensions of the tyres are indicated by the numbers. The tread width in millimetres is 205. Since the aspect ratio is 40, the sidewall height is 40% of 205mm, or roughly 82mm. R17 indicates that the tyre is compatible with 17 inch wheels. This size is found on a variety of vehicles, from sportier compact models to daily hatchbacks. It is frequently selected in situations where improved cornering and a firmer ride are important. High-end manufacturers like Michelin and Continental offer this size; the Michelin Pilot Sport 5 and the Continental UltraContact in 205/40 R17 are two examples. Hankook, Yokohama, Kumho, and Toyo are examples of mid range options. Finally Wanli, Dynamo, and Nankang are value brand options. Confirm it's right for your car by checking the tyre sidewall, the driver's door sticker or your vehicle handbook, or enter your registration for exact matches.

The first 3 sets of numbers that you will see when reading a tyre size tell you the width, profile and diameter of your tyre. In this case, for the tyre size 205/40 R17 this is broken down as follows: 205 - the width of the tyre in millimetres. In this case 205mm wide. 40 - the height of the sidewall as a percentage of the width. In this case 40% R17 - the diameter of the tyre's inner rim in inches. Essentially what size of wheel this is intended to be fitted onto. For this size, that is a 17 inch wheel

If you are looking for the recommended tyre pressure for 205/40 R17 tyres, you will find that this will depend on the manufacturer and model. Each vehicle manufacturer has their own tyre pressure recommendation for their model, that will deliver an optimal performance for your vehicle. Check the following if you are unsure what the correct tyre pressure is for your 205/40 R17 tyres Tyre label - this is often the best place to find your tyre pressure information. It is located on the door jamb on the driver’s side of the vehicle. It is a small rectangular label that provides the driver with the recommended tyre pressure and tyre sizes. Vehicle handbook - Quite often the vehicle handbook with contain a section that relates to the technical details for the tyre. This should include the required tyre size, load rating, speed rating and recommended tyre pressure.

The sidewall height of a 205/40 R17 tyre is calculated by using the profile information of the tyre size. In this instance 40. This tells us that it is 40% of the tyre's cross-section width. When looking at a tyre, the sidewall height is the distance between the tread line of the tyre and the rim line. Given that this tyre size has a cross-section width which equals 205mm, we can work out that the sidewall height is 40% of 205 – this comes to 82mm.