Falken ZE912 or Kumho KU31

[Dogbreath]

Besides, a set of 452's is hardly expensive!

They aren't but then perhaps he needed something that was available locally? I've been in that situation and it surprising how difficult it is to find places with stock of the less popular tyre sizes in a specific brand and model.

 

[[TW]Fox]

I think you will find the only difference is what they claim is the use of the tyres. One is designed as a no compromises road performance tyre, the other is designed as an all rounder with comfort and safety in mind.

I 100% agree that for performance driving the 452 is superior, no doubt in my mind, where available and performance driving is the goal, get it. Where I fail to agree with you at all is that the 912 is inherently less safe than the 452 for general driving and in the event of an emergency, and nowhere do Falken claim the 452 is superior to the 912 in safety and this is my point and where I fail to see yours.

Err to be fair, safety = not losing grip. The more grip, the more safety. Therefore if a tyre offers more grip, it is therefore a safer tyre. This is pretty basic.

 

[[TW]Fox]

They aren't but then perhaps he needed something that was available locally? I've been in that situation and it surprising how difficult it is to find places with stock of the less popular tyre sizes in a specific brand and model.

I dont think I'll start the whole 'how can you not know in advance, unless you get a nail, that you might need tyres soon' thing in this thread

 

[Dr Who]

Err to be fair, safety = not losing grip. The more grip, the more safety. Therefore if a tyre offers more grip, it is therefore a safer tyre. This is pretty basic.

And this is where you fail, as the 452 does not have increased grip, increase steering feel, yes, increased road noise, yes, increased steering response, yes, increased grip, no.

2nd point, increased grip (or the illusion you have increased grip) leads to over confidence and more risk taking, therefore an overall decrease in safety.

This is like the old comparison of airbag vs huge spike on the steering wheel.

1 is safer, 1 makes you drive more safely.

 

[[TW]Fox]

And this is where you fail, as the 452 does not have increased grip, increase steering feel, yes, increased road noise, yes, increased steering response, yes, increased grip, no.

So outright grip on the two tyres is identical? There are no differences in grip whatsoever? Forgive me if I dont take your word for that!

2nd point, increased grip (or the illusion you have increased grip) leads to over confidence and more risk taking, therefore an overall decrease in safety.

So now you are saying tyres with less grip are safer as they reduce driver confidence, there have been some crackers in this thread, thats for sure..

 

[DM]

So outright grip on the two tyres is identical? There are no differences in grip whatsoever? Forgive me if I dont take your word for that!

Its an important point if its right though.

 

[Dr Who]

So outright grip on the two tyres is identical? There are no differences in grip whatsoever? Forgive me if I dont take your word for that!

So now you are saying tyres with less grip are safer as they reduce driver confidence, there have been some crackers in this thread, thats for sure..

No I am sure you will take some reviews off the internets word instead, I care not. I would actually expect each tyre to be slightly superior to the other in certain circumstances which is normal as they are different compounds and patterns, but similar overall yes. If they were identical then there would be no reason for the other to exist.

No I am saying that tyres that give the illusion of more grip lead to more risk taking, you know this but are choosing to be obtuse.

 

[JamesRJ]

Cheers for all the input but as Fox says I have got the tyres now and I'll have to live with them.
I'm currently doing a 180 mile a day commute until I move, so I just join the A38 and set cruise control, its not being used hooning around lanes.
I can see Foxes side of the argument, in fact when I had an Elise I would only fit Yokohama Advan Neova Lotus spec tyres. I bought the car based on its phenomenal handling so why fit cheap tyres and compromise that ?
I bought the BMW to make commuting more bearable not for maximum G'sss I could obtain going round a bend.
I didn't budget on £100 each I just didn't want to spend more than that.

 

[Dr Who]

Cheers for all the input but as Fox says I have got the tyres now and I'll have to live with them.
I'm currently doing a 180 mile a day commute until I move, so I just join the A38 and set cruise control, its not being used hooning around lanes.
I can see Foxes side of the argument, in fact when I had an Elise I would only fit Yokohama Advan Neova Lotus spec tyres. I bought the car based on its phenomenal handling so why fit cheap tyres and compromise that ?
I bought the BMW to make commuting more bearable not for maximum G'sss I could obtain going round a bend.
I didn't budget on £100 each I just didn't want to spend more than that.

And that is my point in a nutshell really.

 

[[TW]Fox]

Its an important point if its right though.

It wont be, though. Two different tyres aimed at two different markets from the same manufacturer offering 100% identical grip? lol

 

[Dr Who]

It wont be, though. Two different tyres aimed at two different markets from the same manufacturer offering 100% identical grip? lol

And I do not claim they are 100% identical, I also do not claim, like you that one is superior in every condition to the other, I claim that overall, they do not offer any significant reduction in grip to compromise safety and in some instances might have more grip.

One will be better on a certain depth of water, one will be superior on a certain type of tarmac, one will be better on a smooth road, one will be better on a rough road, one will be better on snow, one will be better on muddy roads. The only thing I will say for certain is it wont be the same tyre each time.

 

[[TW]Fox]

I bet that in every given circumstance involving grip (ie aquaplaning, wet braking, dry braking, lateral grip, etc etc) the 452 will be superior to the 912. Thats the point. It's why it exists - it is the highest performance tyre that offers superior performance in all situations BUT trades this off against fuel economy, longevity and more importantly price. This is why its only offered in the larger, higher end tyre sizes whereas 912, as a multi purpose budget tyre, is available across a broader tyre size range, focused mostly on mid range cars.

The 912 is inferior in every way - but lasts longer and costs less. Thats its point.

Same with any other manufacturer - a Premium Contact is never a more grippy tyre than a Sport Contact but is wears less, costs less, is available in smaller sizes, is more comfortable and so on and so forth.

Performance = grip.

 

[Dr Who]

I bet that in every given circumstance involving grip (ie aquaplaning, wet braking, dry braking, lateral grip, etc etc) the 452 will be superior to the 912. Thats the point. It's why it exists

Performance = grip.

Firstly, the 912 is a newer tyre than the 452, so some improvement in compound and technology is involved, I am sure in teh tyre that replaces the 452 that tech will improve the 452 by a similar amount.

Next aquaplaning has NO grip, no matter what the tyre, you are deluded if you think one offers more grip when aquaplaning.

What different tyres do is have a resistance to aquaplaning based on how much water they can clear, as a general rule of thumb, the tyre that can cut thru the water will have more resistance to aquaplaning, that involves using tread patterns that are sub optimal in the dry. This is one area where the 912 scores above the 452 which acts more like a sledge due it its far stiffer carcass and older symmetrical design, Additionally a harder compound is used in this case to stabilise the tread and how it cuts thru the water to minimise aquaplaning.

Dry grip, this involves putting as much rubber on the road as is possible and having that rubber as stable as possible, blocks moving around under cornering can have less feel and are sub optimal for driver feedback, but are far more forgiving on some road surfaces, this is where the 912 is inferior to the 452, as the 452 will use a softer compound and highly stable block pattern to maximise dry weather grip.

Stiffer Carcass, a stiff tyre gives more accurate feedback to the driver and also gives improved response to steering inputs, this is almost demanded by a performance driver and failure to deliver this leads to the driver feeling less involved. This however can be tiring over longer drives so is sub optimal for longer journeys over highway style roads. It can also be less forgiving on bumpy surfaces. The 452 is a stiffer tyre than the 912 and is designed to give more feedback to a performance driver, it gives best results on a smoother surface where its tread pattern maximises surface contact and minimises tyre deflection under hard cornering.

Essentially the 452 is a high performance "summer" tyre and the 912 is an "all season" tyre, as a result, the 452 excels in the dry and the 912 is an improvement in the wet.

I could go on, but I really cannot be bothered, if you truely believe that 452's are better in every circumstance than 912's then I will never convince you and I don't even care to try, for those with a less closed mind, the above information may help you decide whether you want a good all round tyre with less than maximum dry grip or an ultimate grip dry weather tyre with some wet compromise for a similar price.

 

[Moeks]

Is it not rather obvious that he meant resistance to aquaplaning? ...of course a tyre doesn't grip the surface of water, if it gets to that stage it's too damn late.

 

[Dr Who]

Is it not rather obvious that he meant resistance to aquaplaning? ...of course a tyre doesn't grip the surface of water, if it gets to that stage it's too damn late.

He possibly did, but a tyre that gives best performance in the dry is unlikely to give best performance in the wet, if it did then they would sell it as an all season tyre and it would become cheaper due to the economies of scale.

EVERY tyre is a compromise in one condition compared to another, and this can change with temperature and wear, this is why the 912 is better in some circumstances and the 452 in others.

 

[[TW]Fox]

He possibly did, but a tyre that gives best performance in the dry is unlikely to give best performance in the wet, if it did then they would sell it as an all season tyre

Why would they? All season tyres are tyres which are also suitable for use in lower temperatures, it's not about whether its raining it not.

Wet weather isn't season dependant. Temperature is - and its performance in varying temperatures that dictates all season tyres.

 

[Moeks]

That has always been my understanding of 'all season' too, that it's temperature dependant more than anything.

No doubt some tyres are better in the rain than others.

 

[Dr Who]

Why would they? All season tyres are tyres which are also suitable for use in lower temperatures, it's not about whether its raining it not.

Wet weather isn't season dependant. Temperature is - and its performance in varying temperatures that dictates all season tyres.

Again wrong

Performance tyres or summer tyres
Performance tyres are designed for faster cars or for people who prefer to drive harder than the average consumer. They typically put performance and grip ahead of longevity by using a softer rubber compound. Tread block design is normally biased towards outright grip rather than the ability to pump water out of the way on a wet road.
All-round or all-season tyres
These tyres are what you'll typically find on every production car that comes out of a factory. They're designed to be a compromise between grip, performance, longevity, noise and wet-weather safety. For increased tyre life, they are made with a harder rubber compound, which sacrifices outright grip and cornering performance. For 90% of the world's drivers, this isn't an issue. The tread block design is normally a compromise between quiet running and water dispersion - the tyre should not be too noisy in normal use but should work fairly well in downpours and on wet roads. All-season tyres are neither excellent dry-weather, nor excellent wet-weather tyres, but are, at best, a compromise.
Wet-weather tyres
Rather than use an even harder rubber compound than all-season tyres, wet weather tyres actually use a softer compound than performance tyres. The rubber needs to heat up quicker in cold or wet conditions and needs to have as much mechanical grip as possible. They'll normally also have a lot more siping to try to disperse water from the contact patch.

Falken claim the 912 as a High Performance All Season Tyre and the 452 as an Ultra High Performance Tyre. Note the lack of all season! Winter Tyres are the ones that work well in ultra low temperatures, they are far superior to all-season tyres.

 

[[TW]Fox]

Again wrong

Really?

From your quote:

All-season tyres are neither excellent dry-weather, nor excellent wet-weather tyres, but are, at best, a compromise.

In contrast, some of the high performance summer tyres are indeed excellent wet weather tyres. You only need take a look at the tread pattern on an Eagle F1 GS-D3 to understand why it offered class leading wet performance.

I am convinced the wet weather performance of a ZE912 would be shamed by almost any premium high performance summer tyre. Sadly though I cannot prove this to you. I've tried to find some data but despite looking through the best part of 20 sets of detailed testing results, not one institution has bothered to test a 912 at all.

 

[Dr Who]

Where did I say that it was as good as other premium tyres? Now it is you putting words in others mouths I have no need for you to try and prove to me a £200 tyre is better than a £100 tyre in a test, that is not in doubt, the dispute here is whether a £100 tyre is worse than a £102 tyre in all conditions, as that is what you are claiming.

Yes the Eagle F1 GS-D3 is a great summer performance tyre and you pay for all that development work, although not all Eagle F1's are as good as each other in the dry right? Good Year F1 All Season for example surpasses the F1 GS-D3 in certain conditions right? So it is impossible the 912 does the same compared to the 452 right? No Wrong!

The F1 GS-D3 is a great grippy tyre, shame they don't make it in 255/35/18 though, shame also that it has poor fuel economy, making the real cost of using them far higher than the outlay as well, although that has little to do with safety so may as well ignore it.

Yes All season tyres are a compromise compared to summer performance tyres they are a jack of all trades and a master of none, which, coincidentally, is perfect for 90% of the drivers on the roads, who dont have time to get spare sets of wheels for the winter with different tyres, or don't want to leave the car at home during the winter, or just plain require an economical tyre that does a reasonable job and is safe in the widest range of conditions.

The thing I fail to understand is why you find it so dificult to admit that the 912 could be better than the 452 in some circumstances, you defy all logic making a claim otherwise, however, it is clearly a point you need to make even though you can back it up with no personal experience.