Choosing The Right Tyres
When replacing your car tyres, it's important to ensure you're selecting the correct size and specification. These details are clearly marked on the sidewall of your current tyres. However, there have been cases where, at some point in the car’s life, the wrong size tyres may have been fitted.
To confirm the correct tyre size and specifications, refer to your car's handbook. This will tell you the original tyre size and type recommended for your vehicle. Using tyres that are not specified for your car can be dangerous, as it can negatively impact handling and overall safety.
Tyre Compatibility and Safety
It’s crucial to avoid mixing different types of tyres on the same axle, as this can be both dangerous and illegal. The only exception to this rule is the spare tyre, which may differ in size or type but is only intended for temporary use.
Run-Flat Tyres
Many modern vehicles come equipped with run-flat tyres, which allow you to continue driving after a puncture for approximately 50 miles, at a maximum speed of 50mph. This is possible because the run-flat tyre is designed to support the weight of the vehicle even without air pressure.
Run-flat tyres are marked with various indicators, including DSST, RFT, ROF, and RunFL, depending on the manufacturer.
Important Considerations for Run-Flat Tyres
Tyresafe recommends that run-flat tyres should only be used on vehicles equipped with a pressure monitoring system. This system alerts you if tyre pressure is low or if a puncture occurs, ensuring that you are aware of any issues while driving.
Understanding Tyre Markings
The sequence of letters and numbers on the sidewall of your tyres provides important information about their size, dimensions, and other features. While these markings can sometimes be challenging to read, they are always present and essential for selecting the correct replacement tyres. Always ensure that you understand these markings to maintain your vehicle’s safety and performance.
Here's what they mean
185 = the tyre width. This is in millimetres.
60 = the tyre sidewall profile, this is the height of the tyre sidewall based on the percentage of its width.
R = the tyre is a radial
14 = the diameter of the tyre/wheel rim. This is in inches.
T = the tyre's speed rating, it is a legal requirement that this must match or exceed the top speed of your car
Here is a list of all tyre speed ratings.
- S 180km/h or 112mph
- T 190km/h or 118mph
- U 200km/h or 125mph
- H 210km/h or 130mph
- V 240km/h or 149mph
- W(ZR) 270km/h or 168mph
- Y(ZR) 300km/h or 186mph
- ZR Above 240km/h or 149mph
Legal Requirements - Tyres
What You Need to Know
To ensure the safety and performance of your vehicle, it’s essential to use the correct tyre size and construction type. While the minimum requirement is to match the size and type recommended for your vehicle, tyre and vehicle manufacturers often collaborate to develop Original Equipment (OE) tyres that are specifically optimized for your car's characteristics. We highly recommend replacing your tyres with OE tyres, as they provide the best performance and safety tailored to your vehicle.
Tyre Tread Depth
The legal minimum tread depth for tyres is 1.6mm across the central three-quarters of the tyre. However, we advise replacing tyres long before they reach this limit. The recommended tread depth for optimal performance is 3mm, as grip significantly decreases below this level. Keeping your tyres within this recommended tread depth not only ensures better safety but also helps you avoid fines and penalty points on your licence.
Tyre Pressure
Maintaining the correct tyre pressure is vital for both tyre health and vehicle performance. Refer to your vehicle’s handbook to find the recommended tyre pressure. Under-inflation or over-inflation can lead to uneven tyre wear, reduced handling capability, and increased fuel consumption.
Tyre Condition
Your tyres should be free from lumps, bulges, or tears in the sidewall. Additionally, there should be no exposed ply or wires visible on the tyre. These are clear indicators that your tyre is compromised and should be replaced immediately.
Tyre Construction and Matching Tyres
It is important to use the same type of construction (radial or cross ply) on the same axle. Mixing tyre types can affect handling and safety. Additionally, avoid fitting tyres with different patterns, such as asymmetric or directional, on the same axle. These tyres are designed to work in pairs to provide optimal handling performance. Some ultra-high performance tyres are asymmetric or directional and are marked with a "left" or "right" label. Ensure these tyres are fitted in their correct position to maximize their performance potential.
By following these guidelines, you’ll help ensure that your vehicle's tyres remain in optimal condition, enhancing safety, performance, and longevity.