New tyres and the tyre labels law

^opm^

After a pair of new front tyres for my focus, the tyres are size 225/4/18 been online doing a few checks and it seems to me that the more expensive tyres are no better under the new tyre labelling indicators then a lot of the cheaper tyres.

Infact found some fully fitted sailun tyres for £64 fitted each that are fuel rated 'b' , rain grip rated 'b' and noise level of 72db , these seem a bargain when i can go up to £200 each michelin that are fuel rated 'f', rain rated 'b' and 73 db noise.

In looking through i cant find a more expensive tyre that beat em, some are a tad quieter, but none are more fuel efficient infact most are a lot worse and non are better in rain.

Think im going to save myself a fair bit of wonga and get the cheap tyres

worried_jim

Have you tried-
http://green-tyres.org.uk/

^opm^

mmm that site is just a site that tells you about the labelling system more then anything else tho

HHarry

My only thoughts are that the new ratings don't say anything about dry weather performance, which is how they'll be used for the majority of the time.
That still doesn't mean that dearer is better, but having had my fair share of 'moments' with cheap tyres, I'd always go for a name now - even if its just a mid-range brand.

Splott

^opm^ wrote: »

After a pair of new front tyres for my focus, the tyres are size 225/4/18 been online doing a few checks and it seems to me that the more expensive tyres are no better under the new tyre labelling indicators then a lot of the cheaper tyres.

Really they are. The letters assigned are meaningless without knowing what the criteria is and also like manufacturers fuel figures, they probably bear no resemblence to reality. They're measured against a "reference tyre" yet I have not so far been able to find the specs of that reference tyre. In addition to that, it measures a very small criteria - three in fact. What that criteria does not measure is cornering performance nor aquaplaning. You get rolling resistance and wet weather performance but again, that doesn't tell you anything. You could have a tyre that corners excellently in the wet but is at best average on wet braking yet it would get a B overall when my opinion is it should get the rating of the lowest result. Also it tells you nothing about the longevity of the tyre either.

In fact the only thing worthwhile in that test is the noise level. A dB is a known value with a rise of 3dB being double the level, 6dB four times the level and conversely a drop of 3dB being half as quiet and 6dB being four times quieter than whatever tyre you're comparing it to.


My favourite Kumho KU31 are supposedly better than the Continentals fitted to my new car but I can guarantee you they're not, especially with the road noise.

GolfBravo

The new tyre ratings are useless. The labels show only 3 criteria (no dry braking, handling, aquaplaning and durability info) and the EU labelling scheme for tyres is based on self-declaration by manufacturers or importers.

GolfBravo

Splott wrote: »

They're measured against a "reference tyre" yet I have not so far been able to find the specs of that reference tyre.

Apparently it is a BF Goodrich (Uniroyal) 225/60 R16 tyre made specifically for the international Standard Reference Tyre Test. Relatively old tyre from 2006.

The whole EU tyre labelling is officially designed to help consumers pick good tyres. The reality is that the EU is planning to implement "noise taxes" - noisy tyres will be subject to additional EU "green" tax - hence the requirement for noise level labels.

GolfBravo

Swedish National Road and Transport Research Institute (VTI) on the Standard Reference Tyre used in the EU Tyre Label wet grip test:

Today, the ASTM has defined a new and more modern tyre of similar type in its standard F2493-06. The wet braking performance of the ASTM E1136 SRTT tyre is very poor, according to several tests made at VTI; it is actually one of the worst measured by VTI [Nordström, 2008]. Therefore, the limits in Table 9 are very liberal and will only remove tyres which would be totally unsuitable for European roads. To comply with such a limit is in no way a proof of quality.

epninety

Splott wrote: »

In fact the only thing worthwhile in that test is the noise level. A dB is a known value with a rise of 3dB being double the level, 6dB four times the level and conversely a drop of 3dB being half as quiet and 6dB being four times quieter than whatever tyre you're comparing it to.

That's not quite correct. A dB is a ratio, not an absolute value, but thats not the important bit.

A rise of 3dB is a doubling of the power present in the sound.
A rise of 6dB is a 4 times the power, but represents double the sound pressure level.

However, a change of 10dB is usually considered to represent a doubling of the perceived volume level that is actually heard. (This 10dB value is a tenfold change in the power, and a little over three times the sound pressure level).

The numbers aren't important really, but if you believe a change of 3dB represents 'twice as loud' you might give undue weight to that number when you choose your tyres.

If 'they' really wanted to encourage consumers to buy 'green' tyres, why is there no relative measure for the life of a tyre in these wonderful new ratings?

forgotmyname

The labelling system is seriously flawed. Otherwise we should all rush out and buy the cheapest chinese nogrip specials you can find.

andygb

^opm^ wrote: »

Think im going to save myself a fair bit of wonga and get the cheap tyres

Please don't!:eek:

From the tyre size which you quoted (incorrectly because an aspect ratio of "4" is incredibly low profile;)), you are driving a Focus ST (?), a high performance hatch which needs top quality brakes and tyres, in order that it steers and stops efficiently.