Tyre labels & speed ratings, explained.
Tyre Speed Rating
The speed rating of a tyre is displayed on the sidewall. Like in the image, you will find it at the end of the tyre's size. It is always represented by a letter - in the following example the tyre speed rating is "W".
Once you know your tyre speed rating, you can work out what is the maximum speed your tyre is capable of maintaining.
For example, the "W" rating seen in the image, tells us that this tyre can reach speeds of up to 168mph.
Speed ratings are based on tests in which engineers run the tyre at 6.2 mph steps, in 10 minute increments, until the required speed has been met.
Effect on Car Insurance
It is very important that you check your speed rating before buying tyres. Choosing a tyre with a lower rating than is appropriate for your car can invalidate your insurance.
If you still have questions regarding speed ratings, do not hesitate in calling our team on 01952 615939
Tyre Labelling explained
Priorslee Motor Services Tyre Label Guide
In November 2012 a new piece of legislation came into force which required the majority of new tyres to come with EU set Tyre Labels. Although the legislation was reported on - to a small degree - in media outlets such as the BBC, there is not a great deal of information out there for consumers. Many important figures within the tyre industry called this new piece of legislation the biggest change to hit the tyre market in over 50 years and they were not wrong. This is why we have spent time developing the following EU Tyre Label guide. We want to help you understand exactly what it is, why it has come to be and how it will affect you.
What is tyre labelling?
As previously mentioned, a new piece of EU Legislation came into force which meant that every new tyre sold within Europe (with some exceptions, but more about that later) must be labelled - much like a fridge, freezer or even light bulb. So, since November 2012 the following label has been seen when shopping for new tyres:
You will notice that it bears a remarkable resemblance to the labels used for electric goods in the EU. However, unlike the electrical labels, the tyre label doesn't focus on energy ratings. It shows you the grade given to 3 important categories that should be considered when choosing a tyre:
- Fuel Efficiency
- Wet Grip
- External rolling noise
Why was it introduced?
The main goal of the new legislation was to provide more information to motorists on the performance of tyres. By doing this, the EU hope to increase road safety, make shopping for tyres more cost-effective and reduce the impact tyres have on the environment.
With each tyre on the market being tested and classified using the same criteria, vehicle owners will now be able to make a more informed decision when shopping for new tyres - with tyres easily comparable for these specific capabilities.
Who does it affect?
Quite simply, it affects everyone. From the tyre manufacturers, to the tyre suppliers and retailers (that'd be us), all the way to the consumer (you!).
For those of us within the tyre industry, we now have an obligation to our customers to ensure that we fully comply with this new piece of legislation. Manufacturers must ensure that the tests they complete are objective and accurate.
They must all ensure that the data required is handed down the chain to retailers. This is so we can fully understand the products we are selling. After all, although these labels are empowering for customers, the tyre label will not give you the full picture, the tyre experts (us again) will.
For you, the customer, the effect of the label is nothing but a good thing. Not only does it allow you to quickly compare the tyres that you are interested in purchasing based on standardised tests, it gives you information that will add confidence to your final decision. Information is power.
Are all tyres included?
At present, no. Not all tyre categories are covered by the legislation, only the following:
- Car tyres
- 4x4 tyres
- Van tyres
- Truck tyres
Tyres Not Covered:
If you are buying racing, professional off road, spare, vintage, re-tread, motorbike or studded tyres, you will not see this label.
EU Tyre Labels: How the tyres are tested
Since June 2012, tyre manufacturers have been required to provide data in relation to the performance of their tyres through testing.
Due to the sheer vast number of tyre models, it was decided that a centralised EU tyre testing facility would be unmanageable and unproductive. Therefore, tyre label testing is self-certified using specific EU standardised methods that every test must adhere to.
Testing Rolling Resistance
A tyre is mounted to a specially designed two-metre drum. It is then rotated with a defined load and pressure.
The test engineers have the torque required to rotate the drum before the tyre is fitted, so they are able to calculate the torque of the tyre by subtracting the new level required when the tyre is mounted against the level when it is not.
It is through calculating the difference of the drum's torque with or without the tyre that they can record what is known as the 'Rolling Resistance Coefficient'. This is what is used to work out the correct grading for the new tyre label.
Testing Wet Grip
There are two tests that engineers are required to carry out to come up with the wet grip rating.
- First of all they need to carry out a wet braking test. This measures the performance of a tyre when a vehicle is braking on a wet surface. The distance that the car travels when slowing from 50mph to 12mph is recorded.
- They also carry out what is known as a skid trailer test. This calculates the friction between the tyre and the road surface. For the tests to be valid, it must take place when the vehicle is travelling at 40mph.
- Once they have both results, they combine them to create the Wet Grip Index (WGI) - this shows the percentage of improved ability compared with an independent reference tyre.
Testing Noise Emission
This test is done to find out the external noise of a tyre in decibels (dB).
The actual test consists of a microphone being set up on the edge of a track to measure the sound level of a test vehicle - the mircophone is required to be 7.5m from the centre of the track at sit at 1.2m above the ground. When passing, the vehicle must be travelling at 50 mph with the engine turned off for the test to be valid.