Tyre ratings....

user1168934

jase1 wrote: »

Also bear in mind that the standards allow for manufacturers to use band "E" to denote a tyre that has not been tested. It does not necessarily indicate poor performance in that area.

Are you sure?
I thought "D" was the one.

stator

I always go for tyres with the best "wet stopping distance". Given how idiotic other people drive in the wet, having decent tyres could save your life.
Unfortunately they don't give you a rating for how quickly the tyres will wear out and reading online reviews won't help you work it out either.

DUTR

stator wrote: »

I always go for tyres with the best "wet stopping distance". Given how idiotic other people drive in the wet, having decent tyres could save your life.
Unfortunately they don't give you a rating for how quickly the tyres will wear out and reading online reviews won't help you work it out either.

It's a similar argument with winter tryes though,
eg you may have great wet stopping tyres on your car, but the vehicle behind may not, so you are still in some element of danger, likewise with winter tyres, if the vehicle infront is stuck in snow, then you are stuck behind them.

bowlhead99

user1168934 wrote: »

I was also getting confused by the same thing as to why its F or even G for fuel efficiency for very good sporty tyres. From what I understood fuel efficiency is directly related to the rolling resistance or the surface area of the tyre in contact with the road. So having an F fuel rating will mean there is probably more surface area in contact and thus more friction which would help with improved handling but will use more fuel. Surely for more sporty tyres you would want more friction for better handling.

If you coated your tyres with super sticky glue before leaving the house each day the tyres would have a tacky surface, and if it was consistent across the whole tyre it would help you avoid sliding as you drove too fast into a corner provoking oversteer or understeer. So, the friction helps you go round corners, which can be a good thing.

It also requires more effort to accelerate, to overcome that resistance, so more fuel gets used. Also as bits of glue/tyre gets left behind on the road surface because it stuck very effectively, you are eroding the outside surface of your tyre and will need to replace the glue every day or just buy the sticky tyres more frequently as they wear down. Also, the tyres might be noisy as there's a lot of rubber hitting and sticking to the road.

In F1 racing you can see that the tyres that do best in the wet are the opposite of the ones that are best in the dry. In your UK road car which has to handle both there's a combination of tread pattern and rubber compound at work. When you're going through a puddle and the tyre surface is cooler a summer compound won't be at its grippiest, let alone the fact that there is a load of water between the tyre and the road surface. Do you want to pass the test for stopping fastest or changing direction fastest or doing better in icy winter or warm wet autumn or do you not care because you're mostly only out in good weather?

There are plenty of factors to consider but while you might prefer scientific evidence over anecdotes, the people doing the tests are the tyre industry members themselves and there will be differences between two tyres that both get a "B" in a category, much as there's a difference in two "size 10" dresses and the approaches of two Grade 'A' students.

If you surf around the car forums you'll see the car mags do independent tests from time to time, although some would question their independence too, given the manufacturers advertise with them and sponsor events and give free or heavily discounted samples. Also different markets have different tyre models e.g. US vs German consumers want different things.

TBH the only way you can really tell if the experience of driving 20-30k miles on a set of tyres is worth the premium cost or the cost saving, is after you've done those 20k miles and also driven many more miles with a different type of tyres with the same car and conditions combo...

Norman_Castle

DUTR wrote: »

How is the informed descion arrived if not through marketing hype or hysteria hype?
I thought the ratings thing was a standardised measure now.
Eg my previous car came with Continental sport contacts, they were fine although some reading said they were rubbish. My current car has Bridgestone Potenzas, again they are fine but some reading says they are rubbish. Only thing with medium and budget tyres is finding many/any reviews. I guess if the tyres were ok for OEM then they are fine to use again? Although I may go all season type.

What does the highlighted parts above tell you about some "reviews". Many are simply opinions from nobodies.

Norman_Castle

forgotmyname wrote: »

The issue is that the tyre manufacturer create the tests to get the ratings so there is some element of "cheating" to obtain a better result.

The manufacturers perform the set tests and their results have to be available for inspection. As an EU directive there are likely to be further tests done if there are doubts about the results. Presumably there are penalties for fraudulent test results.

The ratings don't tell buyers everything about tyres but before them there was only reviews, opinions and advertising. All of these could be biased in some way.

forgotmyname

https://www.tyremen.co.uk/help-advice/tyre-labelling

Autoexpress did another tyre test recently and find that some tyres in the same group have much less grip compared to others.
B rated tyres for wet grip yet takes an extra 4 metres to stop?

Tyre noise also, Why was the 72dB rated tyre the quietest even over a 68dB one? with the others all being 69dB but louder?


rates at 69

Iceweasel

Many of these tyre tests and comparisons are so subjective as to be near meaningless.

All tyres are a compromise - no tyre yet made has high grip, low wear, low noise and gives a comfortable ride - so what makes a 'good' tyre is up to the user and what they consider to be the priorities for their particular set of circumstances.

DUTR says he has experience of ContiSportContacts and Bridgestone Potenzas - both of which he found to be 'fine' although there were mixed/conflicting reviews on both.

I also have experience of both of those and didn't fine either of them 'fine'.

The Bridgestones were absolute rubbish - noisy, bumpy, wore at a high rate, squealed on hard cornering etc. etc. - I'd never buy them again, and if I bought a car with them I'd change them right away.

The ContiSportContact 2s that I currently have are much better than 'fine' - they are exceptionally good - absolutely excellent with fantastic grip in both the dry and the wet, plus they seem to be going to last longer and they are £2 cheaper at £72.50 each.

Of course the latest current generation/state of the art ContiSports are reported to be a great improvement on what I am running - but they don't produce CSC6s in my size, so I can only fit CSC2s.

That's not to say that I think DUTR is wrong or mistaken in any way - his criteria will likely be different from mine so what is acceptable or'fine to one driver may be pretty poor to another.

My advice would be to stick with what you know and not change brand simply on the basis of tyre ratings or reviews.

DUTR

Iceweasel wrote: »

Many of these tyre tests and comparisons are so subjective as to be near meaningless.
snip


My advice would be to stick with what you know and not change brand simply on the basis of tyre ratings or reviews.

The thing is, the car is curently running Bridgestone Potenza, They have gone through 2 winters without fuss, if I were to change it maybe for some mid range, but as many suggest the 'gain' in fuel effeciency will be negligible compared to grip which is obviously more important in those mad moments

Iceweasel

DUTR wrote: »

The thing is, the car is curently running Bridgestone Potenza, They have gone through 2 winters without fuss, if I were to change it maybe for some mid range, but as many suggest the 'gain' in fuel effeciency will be negligible compared to grip which is obviously more important in those mad moments

The thing is that both ContiSports and Potenzas are summer tyres and as such are pretty useless in snow and in low temperatures - my Contis also become quite hard and feel 'bumpy.'

But if you find that they were OK 'without fuss' then that's fine.

Have you ever driven on real winter tyres designed for all winter conditions - not just fresh snow? Many folks run them all year round in preference to having 2 sets of tyres/wheels.

If I were to have only one set of tyres they would have to be winters - the disadvantages of winter tyres in summer is nothing compared to the advantage in winter.

I understand exactly what your predicament is - a cheaper tyre with full tread will give better results that a worn out premium tyre.

Unless you plan to change the car soon - I'd stick with what you know.