Tyre ratings a,b,c,etc

[jvr]

Looking at buying some tyres and we all know that most of the cheap eastern ones are ditch finders in the wet....or are they?
Now i've got some acceleras on the front at the moment which I inherited but on a previous vectra they were damn right dangerous in the wet.

On the new ratings for performance in the wet,noise etc it would seem that some of the cheapies are the same as the premium brands.

Is it tyre snobbery or are the cheapies officially as good?

Ive got a fwd 3.0 peugeot so grip is quite important.

Confused

P

[JakeT]

I am sure it depends on the car. If you're running them on a small light car it will most likely make less difference than on a large SUV.


But in short I would say stick a set of contis or michelins on the car. They wear well and are known good tyres. Nexens are good budgets also.

[jvr]

So how do they come to the rating conclusion?

[anonymous-user]

JakeT said:

But in short I would say stick a set of contis or michelins on the car. They wear well and are known good tyres. Nexens are good budgets also.

Whereas Ive had Contis on several cars as factory fit and found them to be the softest, quickest wearing of any tyre known to man, I think they use chocolate in the compound.

The ratings don't tell the whole story, wet braking, noise (which is never a factor for me when buying a tyre) and fuel efficiency (again not the most important) - what about comfort, dry performance, snow performance, progressiveness, feedback, wear etc etc.

I find tyrereviews.co.uk pretty useful.

[B3MX5]

Current car I've only fitted Michelin Pilot Sports to, had two fitted today in fact. Previously I've used Toyo's on a similar car, and the difference is very significant - grip, feel, noise are all much improved, but also tyre life is a lot longer. Expensive tyres to buy aren't necessarily more expensive in the long run.

[Mr2Mike]

jvr said:

So how do they come to the rating conclusion?

Self certified by the manufacturer...

[BritishRacinGrin]

Mr2Mike said:

jvr said:

So how do they come to the rating conclusion?

Self certified by the manufacturer...

Tells you all you need to know about the ratings. Surprise surprise Premium tyres are still premium tyres and mid-range are still by and large mid range.

[Andyjc86]

Whilst the ratings don't mean too much in practice, you want them closer to A for wet grip and F for fuel efficiency. Nose ratings are all pretty much the same 70-72db

[BritishRacinGrin]

Andyjc86 said:

you want them closer to A for wet grip and F for fuel efficiency.

What's your theory behind this?

Andyjc86 said:

Noise ratings are all pretty much the same 70-72db

Nay. I've seen as low as 68db and as high as 75.

[kambites]

Plus don't forget decibels is a logarithmic scale. 75db is about five times as loud as 68db.

As for wet grip levels, I'd tend to trust the big magazine group tests over the labels on the tyres. In my experience there is a correlation between price and grip but it's not as strong as some people make out. Some of the better mid-range tyres will out-brake many of the premium tyres.

[TA14]

BritishRacinGrin said:

Andyjc86 said:

you want them closer to A for wet grip and F for fuel efficiency.

What's your theory behind this?

It's not a bad theory. The step between each letter for fuel efficiency is about 1% and not all of the letters from A to F are used so an F is not much worse for fuel economy than an A but taking a few more metres to stop in the wet or losing it on a corner or avoidance manoeuvre could be catastrophic. Of course an A in each would be best.

[BritishRacinGrin]

So the assumption is that a more fuel efficient tyre will have a longer stopping distance?

[Andyjc86]

BritishRacinGrin said:

What's your theory behind this?

The best rating for wet grip is A, so you always want to be on that side of the scale. Fuel efficiency is determined by the rolling resistance, the greater the resistance, the less efficiency. Resistance usually means more grip.

BritishRacinGrin said:

Nay. I've seen as low as 68db and as high as 75.

That's why I said most, not all

[aka_kerrly]

Mr2Mike said:

jvr said:

So how do they come to the rating conclusion?

Self certified by the manufacturer...

Which I find amazing.

Aside from Auto bild it is rare to come across any kind of proper scientific testing of various tyres in a semi controlled environment. Tyre Review websites are often a load of rubbish in my opinion, mostly people who want to brag about buying expensive tyres and those who buy cheap and feel they have to justify them by saying their Wanlis are the best thing they have ever tried.

[Horse Pop]

The wet grip only tests straight line braking in the wet.

The noise is a driveby rating so pretty meaningless for you.

The fuel economy rating is a tiny, tiny margin so again, meaningless.

[jon-]

Horse Pop said:

The wet grip only tests straight line braking in the wet.

Exactly this.

I've tested an A vs and F in wet grip.

Braking, as you expected, the A stopped shorter than the F.

Wet cornering, the F had more grip.

As usual, read reviews relevant for your car (www.tyrereviews.co.uk etc)