Tread pattern vs. compounding for rain/wet grip??

[dailydriver]

I am somewhat confused as to just how much of a role each of these has when it comes to wet road grip (either standing water OR just wet roadways).

It seems some tires (especially the UHP/Max/Extreme varieties from Michelin and Goodyear, as well as some others) with VERY 'tready', relatively small tread blocked, "high void", tread patterns are rated absolute garbage in the wet!!

Are their compounds solely responsible for this, or is something else a factor (besides stiff sidewalls/carcass constructions, etc.)??

Others (like the Nitto NT-01, Toyo R888, Falken 615K, Hankook TD, etc.) obviously HAVE TO BE horrendous in the wet, regardless of how soft/sticky their race/race-like compounds, since they are just slightly 'cut' slicks.

Capri Racer?? Others?

 

[oggb]

Tread design is what gets you by in the rain for the most part. You have to allow the tread blocks to push the water into the voids in the tread design. The more efficient this mechanism is, the better the tire will perform in wet weather.

Compound does still matter - a tire made of plastic obviously won't grip as well as a tire made out of bubblegum, but without proper tread design the compound is just an afterthought.

 

[bepperb]

It's a two part problem with tread design responsible for hydroplaning resistance but tread compound for traction against a wet surface.

The UTQG ratings are traction are graded against a wet concrete surface, and usually only performance tires get a AA rating as they don't have a long wearing rubber compound. On the other hand, find me a slick tire that advertises hydroplaning resistance.

 

[jaj]

Originally Posted By: dailydriver
I am somewhat confused as to just how much of a role each of these has when it comes to wet road grip (either standing water OR just wet roadways).

It seems some tires (especially the UHP/Max/Extreme varieties from Michelin and Goodyear, as well as some others) with VERY 'tready', relatively small tread blocked, "high void", tread patterns are rated absolute garbage in the wet!!

Are their compounds solely responsible for this, or is something else a factor (besides stiff sidewalls/carcass constructions, etc.)??

Others (like the Nitto NT-01, Toyo R888, Falken 615K, Hankook TD, etc.) obviously HAVE TO BE horrendous in the wet, regardless of how soft/sticky their race/race-like compounds, since they are just slightly 'cut' slicks.

Capri Racer?? Others?


I'm not understanding your question, and with 10 years of track experience in my various daily drivers, I have researched the question a lot.

First, who says the UHP/Max/Extreme varieties don't perform well in the wet? Under what usage are they disappointing?

From my experience, what I know is that some rubber compounds work well on wet pavement and others don't. For instance, contrary to your proposition above, Nitto NT-01's are very good on wet pavement - I was running well over 100mph and pulling over 1 lateral G and 1 G braking yesterday at a wet trackday on a set of NT-01's that had very little tread pattern left. No problems to report. However, there have been other days at other tracks where I've returned to the paddock to sit out a downpour when I was running the same set of tires. You have to use your judgment in this stuff.

If the tire tread face loses contact with the pavement - hydroplaning - then the whole equation changes and you have no grip at all. The design of the tread determines how fast you can go before this happens. A high void ratio and many sipes will improve this performance at the expense of ultimate grip. Low void ratio tires like my NT-01's require vigilance.

High void ratios and many sipes also reduces the tire's tread stability, so if it's doing its job to remove water and keep the tread touching the pavement, it hampers the ultimate level of grip delivered in both dry and wet conditions. It won't produce the cornering forces of low void ratio tires that have a comparable compound.

So, my belief is that if you have a tread compound that will produce good grip on wet pavement, then the simplest and lowest void ratio tread design that still clears the water fast enough will produce the highest ultimate grip. The tradeoff is that you will be speed limited when water starts collecting on the road surface.

 

[Indydriver]

UTQG ratings are useful when comparing tires from the same manufacturer. DO NOT expect them to be useful comparing one against another.

So, if you are comparing tires within the Bridgestone Potenza line for example, the AA traction rating really means something over an A or a B. My MS3 came with OE Potenza 050s rated 140 A A. Using the Bridgestone Tire Advisor, I now find that the Potenza S-04 is rated 280 AA A and, checking Tire Rack, I find that it is also a little cheaper. Better wet traction and twice the wear life at a cheaper price? Sounds like a no-brainer to me. So, I will probably try the S-04s when I need new summer rubber next year.

Also, some manufacturers websites are helpful. For example, if you do a search for tire recommendations for your model vehicle on the Bridgestone site, you will get their ratings for each tire on wet and dry grip, road noise, ride comfort, etc.

 

[bourne]

Wet traction is usually influenced mostly by the tread design , open tread with big channels help efficient pumping for water. The pressure between the road surface and tires is usually enough to "push" water into these grooves , allowing the rubber compound to do its job.

Now the second part comes in , if you have an efficient tread design but [censored] compound ( Falkein Zeix 912 to name one ) , like jaj mentioned , when you do cross the threshold of adhesion and your treads get overwhelmed with water, its this compound that decides whether you go into a tank slapper or a mild drift around the corner.

My experience with Falkeins has been such, around city wet driving even in the pouring rain wasnt too bad, but come hwy speeds , when your contact patch is smaller due to higher speeds, when there was TOO much water on the road , the tires would immediately lose grip , this is when tread depths were between 9-10/32nds.

I now have Goodyear Comforttreds ( another touring tire like the falkeins ) , and this is the biggest difference. The limit of traction isnt necessarily higher ( maybe 10~15%) , but when the tread gives , the compound makes for a very predictable slide , easy to control , no drama . To me , thats worth the premium over the Zeix 912s .

 

[rpn453]

I don't think I could tell you anything you don't know, but I'll put my thoughts down.

The wetter it is, the more the tread design matters. As it dries, compound becomes the dominant factor. Both are always important though.

The more tread you can put in contact with the road surface while still maintaining adequate temperature and without hydroplaning, the better. As long as the tire can make good contact with the road, it's down to tread compound.

If a tire with plenty of tread void doesn't perform well in light wet conditions, I think you'd have to blame the tread compound. It may just be too compromised to work really well in any single condition. If a tire with small tread blocks and plenty of void area is made soft enough to provide good traction on a cold, wet surface, it will probably have poor treadlife and suffer greatly during hard driving in hot weather.

 

[rpn453]

Looking at F1 tires, the full wet tire (blue) has a similar tread design to an all-season street tire. It would be destroyed by a single lap in the dry. So they probably have to make that style of tread quite hard on a street tire to provide suitable life for most users. The F1 version is probably just as soft as the Super Soft slicks (red) since it will only ever be used in heavy rain.

The intermediate tire (green) has a similar tread design to a summer street tire. It might make two or three hard laps in the dry. A street version wouldn't get torn up nearly as badly under hard driving as an all-season, so they can make it softer than that. Once again, the F1 version is probably very soft since it will only ever be used when the road is wet and they don't worry too much about how badly it would get chewed up in warm, dry conditions.

The slicks are completely non-functional with any amount of surface water.

I think tires for street use are simply heavily compromised to provide adequate tread life and handle many different operating conditions adequately while excelling at none.

In F1, if you don't match the right tread design for the conditions at the right moment, you're going to lose a lot of time. All of those tires work very, very poorly outside of their intended operating conditions.

 

[CapriRacer]

Wow!!

It's terrific that there are so many really good explanations.

Yup, wet traction can be divided into 2 components - hydroplaning and grip.

Hydroplaning is all about tread pattern. Circumferential grooves have the greatest effect with cross grooves and sipes lagging behind. Directional tread patterns are a little help, but the operative word here is "little". The average driver won't notice the difference.

Grip is all about tread compound - and there is a technology triangle - Treadwear, Traction (especially wet traction), and Rolling Resistance.

Obviously, the more rubber you can put on the ground, the better the grip, but the more likely the hydroplaning. So there is a balance that has to take place.

I am going to take issue about not comparing UTQG ratings between tire manufacturers. ALL the tests are a comparison to to a standard tire - the SAME tire. NHTSA routinely monitors the ratings for compliance. They CAN'T be over-stated, and there is an obvious advantage to stating high values. There is some variability to the tests and the tests are difficult to conduct - requires specialized equipment and highly trained test personnel.

I think that proper way to state the issue of the UTQG ratings is that you have to take them with a grain of salt - especially the treadwear rating. The treadwear rating is pretty fine increments (20 units) and whne you are discussing the difference btween a 600 and a 620 - that's hardly any difference at all.

But traction ratings only have 4 grades - and I think you can have pretty good confidence in the rating. Just be aware that the rating is on a particular surface at a particular facility. Other facilities have different traction values and you can get reversals when you rank order different tires - but the problem is not peculiar to one tire manufacturer.

And the F1 tires? The wet grip tires are incredibly soft - and they have terrific grip in both the wet and the dry - BUT - in the dry they heat up so fast, the rubber breaks down quickly, making them useless. As the tires move to less and less ultimate grip, the tread compound generates less and less heat - so the degradation occurs less rapidly.

By the time they get to the dry compounds, it all about managing the heat buildup. Go too fast and the compound degrades due to heat. Not to mention the affect the car has on the heat buildup. This is today's biggest F1 challenge - tire management!

 

[dailydriver]

Originally Posted By: rpn453
If a tire with plenty of tread void doesn't perform well in light wet conditions, I think you'd have to blame the tread compound. It may just be too compromised to work really well in any single condition. If a tire with small tread blocks and plenty of void area is made soft enough to provide good traction on a cold, wet surface, it will probably have poor treadlife and suffer greatly during hard driving in hot weather.


THIS^^^ is mainly what I was asking about!

A specific example was the OE Goodyear on the C5 Z06 vettes, the Supercar F1; VERY cut/siped/BIG void ratio/relatively small blocks, etc., yet it had a rep for being useless in the wet.
Too 'hard' a compound, even at a 220 treadwear rating, or just too wide???

 

[dailydriver]

Capri Racer;

Let's compare a Michelin Super Sport, to a BFG G-force Super Sport Comp 2.

As far as compounding ONLY goes (taking carcass/construction/sidewalls/etc. out of the equation), are they NOT that far apart, one being a 300 t.w., and the other being a 340, especially coming from the same parent company's labs???

BTW; has anyone installed/used one of these very new BFGs yet?

 

[Rand]

cant compare treadwear utog numbers between manufacturers.

 

[bourne]

Originally Posted By: CapriRacer
Wow!!

It's terrific that there are so many really good explanations.

Yup, wet traction can be divided into 2 components - hydroplaning and grip.

Hydroplaning is all about tread pattern. Circumferential grooves have the greatest effect with cross grooves and sipes lagging behind. Directional tread patterns are a little help, but the operative word here is "little". The average driver won't notice the difference.

Grip is all about tread compound - and there is a technology triangle - Treadwear, Traction (especially wet traction), and Rolling Resistance.

Obviously, the more rubber you can put on the ground, the better the grip, but the more likely the hydroplaning. So there is a balance that has to take place.

I am going to take issue about not comparing UTQG ratings between tire manufacturers. ALL the tests are a comparison to to a standard tire - the SAME tire. NHTSA routinely monitors the ratings for compliance. They CAN'T be over-stated, and there is an obvious advantage to stating high values. There is some variability to the tests and the tests are difficult to conduct - requires specialized equipment and highly trained test personnel.

I think that proper way to state the issue of the UTQG ratings is that you have to take them with a grain of salt - especially the treadwear rating. The treadwear rating is pretty fine increments (20 units) and whne you are discussing the difference btween a 600 and a 620 - that's hardly any difference at all.

But traction ratings only have 4 grades - and I think you can have pretty good confidence in the rating. Just be aware that the rating is on a particular surface at a particular facility. Other facilities have different traction values and you can get reversals when you rank order different tires - but the problem is not peculiar to one tire manufacturer.

And the F1 tires? The wet grip tires are incredibly soft - and they have terrific grip in both the wet and the dry - BUT - in the dry they heat up so fast, the rubber breaks down quickly, making them useless. As the tires move to less and less ultimate grip, the tread compound generates less and less heat - so the degradation occurs less rapidly.

By the time they get to the dry compounds, it all about managing the heat buildup. Go too fast and the compound degrades due to heat. Not to mention the affect the car has on the heat buildup. This is today's biggest F1 challenge - tire management!



you sir unfortunately are incorrect. The ratings are Manufacturer specific, therefore only relevant when comparing tires from the same company. All ratings are in relation with ONE unique "base tire" which no one has really seen. Its locked away in that respective company's secret vault somewhere. Therefore , even when a Kumho or Yokohama is rated at a treadwear rating of like 600 , a bridgestone with a 440 rating might very well outlast that tire. Tire ratings are what the Manufacturer wants to say they are, not what they are tested as.

No such test/board exists which has one unified tire rating or that provides tire ratings in the same reference plane across the market.

 

[CapriRacer]

Originally Posted By: bourne
You, sir, unfortunately are incorrect. The ratings are Manufacturer specific, therefore only relevant when comparing tires from the same company. All ratings are in relation with ONE unique "base tire" which no one has really seen. Its locked away in that respective company's secret vault somewhere. Therefore , even when a Kumho or Yokohama is rated at a treadwear rating of like 600 , a bridgestone with a 440 rating might very well outlast that tire. Tire ratings are what the Manufacturer wants to say they are, not what they are tested as.

No such test/board exists which has one unified tire rating or that provides tire ratings in the same reference plane across the market.


Here we go again!

Here's a link to the actual regulation:

http://www.gpo.gov/fdsys/pkg/CFR-2005-title49-vol6/pdf/CFR-2005-title49-vol6-sec575-104.pdf

There is a prescribed test procedure and a prescribed course monitoring tire. The current course monitoring tire is a P225/60R16 Uniroyal. I don't know exactly how to buy this tire, but the tire testing folks don't seem to have a problem. If you want I will ask.

 

[CapriRacer]

Originally Posted By: dailydriver
Capri Racer;

Let's compare a Michelin Super Sport, to a BFG G-force Super Sport Comp 2.

As far as compounding ONLY goes (taking carcass/construction/sidewalls/etc. out of the equation), are they NOT that far apart, one being a 300 t.w., and the other being a 340, especially coming from the same parent company's labs???

BTW; has anyone installed/used one of these very new BFGs yet?


This gets into the area where the marketing folks live. They want to characterize tires so they can sell them. Sometimes that means adjusting the rating so ithe tire is place where the marketing folks want it to be placed. The key is that the rating can be adjusted DOWNWARD, but not upward.

Like I said, I wouldn't pay much attention to the ratings when they are close. The difference btween a 600 and a 400 would evident regardless oof the manufacturer.

 

[cp3]

Originally Posted By: CapriRacer


Here we go again!

Here's a link to the actual regulation:

http://www.gpo.gov/fdsys/pkg/CFR-2005-title49-vol6/pdf/CFR-2005-title49-vol6-sec575-104.pdf

There is a prescribed test procedure and a prescribed course monitoring tire. The current course monitoring tire is a P225/60R16 Uniroyal. I don't know exactly how to buy this tire, but the tire testing folks don't seem to have a problem. If you want I will ask.

Well at least I know it's not just me! I was told I was wrong when I brought up comparing treadwear ratings too. If they were completely meaningless why are they there?

 

[bourne]

Originally Posted By: CapriRacer

Here we go again!

Here's a link to the actual regulation:

http://www.gpo.gov/fdsys/pkg/CFR-2005-title49-vol6/pdf/CFR-2005-title49-vol6-sec575-104.pdf

There is a prescribed test procedure and a prescribed course monitoring tire. The current course monitoring tire is a P225/60R16 Uniroyal. I don't know exactly how to buy this tire, but the tire testing folks don't seem to have a problem. If you want I will ask.


Please go ahead and read it again. Here is a Quote from there : "The treadwear grade is a comparative rating
based on the wear rate of the tire when
tested under controlled conditions on a specified
government test course. For example, a
tire graded 150 would wear one and one-half
(11⁄2) times as well on the government course
as a tire graded 100. The relative performance
of tires depends upon the actual conditions
of their use, however, and may depart
significantly from the norm due to variations
in driving habits, service practices
and differences in road characteristics and
climate."

Again , like I said , each company has its OWN base tire. Henceforth the relative reading from Bridgestone wont compare to the relative reading of Goodyear. I sell tires for a living , I make it a point to know my product. The ratings only exist so that tire manufacturers have SOME sort of a quality criteria they have to meet. Meaning as long as a tire meets the requirements the manufacturer shoots for " traction, temperature and treadwear " , they do not have to test it any more, neither do they have to submit it for any more testing.

A tire rated A might very well work as an AA rated tire, the company just chose to place it in the market with an A rating. Here is an example, we sell Goodyear Wrangler Silentarmors at work , rated for 50k treadlife rating. I know of at least 10 different customers , who in regular everyday driving , maintained their alignment and rotated regularly, got 70k+ miles with tread left to spare.

Wanna explain why Michelin with a treadwear of 500 is warranting their tires for 60k , compared to Goodyears with 520 rating warrantied for 50k ?

Michelin

Goodyear Silent Armour

Or why this General tire with a 640 Treadwear rating is only warrantied for 40k for H rated of higher , yet the treadwear spec is the same for almost all tires ???

General

One more example, three tires in 205-60-16 size
Goodyear Comforttred : 640 A B 70k warranty
Hankook Optimo H727 : 700 A B 100k warranty
Bridgestone Serenity : 740 A A 70k warranty

Now as an uninformed consumer , if you walk into a tire store , which tire looks to give you the best value for your money ? And what makes you think you will get that value ??

so to summarize , UTQG ratings are more similar to minimum requirements and are relative , effective when comparing tires made by the same manufacturer , not so much when trying to compare two DIFFERENT manufacturers.

 

[OVERKILL]

Originally Posted By: bourne

Again , like I said , each company has its OWN base tire. Henceforth the relative reading from Bridgestone wont compare to the relative reading of Goodyear. I sell tires for a living , I make it a point to know my product. The ratings only exist so that tire manufacturers have SOME sort of a quality criteria they have to meet. Meaning as long as a tire meets the requirements the manufacturer shoots for " traction, temperature and treadwear " , they do not have to test it any more, neither do they have to submit it for any more testing.



You are arguing with a guy who designs tires however......

https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showprofile&User=1045

Occupation: Tire Engineer

http://barrystiretech.com/credentials.html

Quote:
I am currently employed as an engineer by a major manufacturer of tires. Some powers that be within the company don't think it is a good idea for people to be posting on the internet. This creates an odd situation for me. On the one side, I have access to a lot of interesting information. On the other side, there is some information that is considered quite proprietary. So I will not identify the company and disguise anything that might help you figure it out. I hope you will understand.
Besides, the information posted here will be generic in nature - It will apply to any tire, regardless of who manufactures it.
I have been in the tire industry - well...... - let's just say it is over 30 years. I've worked in manufacturing, design, testing, and my current assignment is quite diverse.
I serve as the technical consultant to the 800 number. I have served on committees for various tire related organizations: Society of Automtove Engineers (SAE), The Rubber Manufacturers Association (RMA), The Tire Industry Association (TIA), the Tire and Rim Association (TRA), etc.
I am a member of SAE, Tire Society, and the Sports Car Club of America (I used to hold a competition license, but it has expired).


I wouldn't be so hasty to dismiss the information CapriRacer has posted

 

[bourne]

Yea I understand all that.

Like I said , I stand beside my point. Here is another "real world" experience from our very own forums

bridgestone tire wear

Im not here to question anyone's credentials. I however cannot accept someone's writing on the internet just because someone created a website and wrote their credentials on there. I am not going to ask him to prove them or anything. I dont really care. On a side note to CapriRacer, I do appreciate the website and the effort to educate everyday customers. Bravo on the effort! I have bookmarked it and will definitely be going over it when I have some leisure time.

What I do care about is doing my best to help my customers. Which is the reason why I put these same questions to our senior engineers, tire techs and corporate trainers. I do believe that I am going to go by what I have been trained on so far. I have made my opinions known , along with evidence. The rest is for upto the users here , whether they follow his advice or mine.

 

[Rand]

your discrepancies can be explained by 2 words..

marketing, warranties

Where is this evidence that they use different reference tires? I see evidence of their marketing departments hard at work.

Originally Posted By: Tirerack
Unfortunately, the rating that is of the most interest to consumers is the one that appears to be the least consistent. While the Treadwear Grade was originally intended to be assigned purely scientifically, it has also become a marketing tool used by manufacturers to help position and promote their tires.


http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=48