To be fair all of those cars are fitted with high performance tyres, and in most cases what are basically cut slicks..
I would say that there is pretty severe degradation in those tires. It's only a 1:07 lap time. 1.2 second degradation over 20 minutes is quite a bit.
I would also guess that these guys were pushing very hard. I run 20 minute stints on performance street tires 4x a day (in about the same temps as that test), and I have no trouble with chunking like that. Maybe my tire is better, I don't know, but that's pretty extreme either way. I ran 7 track days on those same tires and drove them on the street every day. They lasted for 18k miles. The last track day on them was marginal. They had lost a lot of grip and I was down a couple of seconds over my normal times.
At the end of the 20 minutes, you can feel the tires getting greasy. You had to back off a bit or you would risk sliding off. But by the next session the tires were OK again. These guys must have just kept pushing hard the whole time with no regard to working with the tire.
Very cool data though. I think it shows us some more interesting tidbits about how tires work.
I would also guess that these guys were pushing very hard. I run 20 minute stints on performance street tires 4x a day (in about the same temps as that test), and I have no trouble with chunking like that. Maybe my tire is better, I don't know, but that's pretty extreme either way. I ran 7 track days on those same tires and drove them on the street every day. They lasted for 18k miles. The last track day on them was marginal. They had lost a lot of grip and I was down a couple of seconds over my normal times.
At the end of the 20 minutes, you can feel the tires getting greasy. You had to back off a bit or you would risk sliding off. But by the next session the tires were OK again. These guys must have just kept pushing hard the whole time with no regard to working with the tire.
Very cool data though. I think it shows us some more interesting tidbits about how tires work.
Nope, the compound of a slick race tyre is VERY different to the compound of a road tyre. A classic example of this is to push a coin edge into a modern "high performance" road tyre (e.g. the Falken RT615's on my Evo 8 MR) and the impression disappears quickly, do that on a slick tyre (I used to get used slicks for use on track days) and the impresson takes a long time to return. This is because the properties of the rubber in the two tyres is very different. A road tyre is expected to do thousands of miles before it's changed, a slick doesn't have anywhere near that life.
I'd guess that's due to the difference in compounds. I do appreciate that road tyres aren't like "slicks" but often resemble cut slicks.. eg the Pilot Sport Cups OE fitment on the M3 CSL...
As your point says, slicks don't have to last, or do they have to work in the cold or, the rain. :o
As your point says, slicks don't have to last, or do they have to work in the cold or, the rain. :o
No guessing required, it is down to the difference in the compounds and construction of the tyre. They are VERY different. A road tyre needs to last a long time and operate under a wide variety of conditions. Race tyres last much less and have a much more specific operating bandwidth.
Actually i've not seen a slick race tyre that is comparable in design to a road tyre. There are obvious similarities between a race wet/intermediate tyre and road tyres simply because techniques in tread pattern often migrate from race to road. However thats where the comparison stops because even though they may look similar, their construction and materials are different.
:rolleyes:
Don't bother he was trying to pretend he didn't say something blatantly stupid and make it look like he "didn't say what he meant". He said "high performance tires were basically cut slicks", you pointed out he's flat out wrong, and now he's trying to save face... again, like in almost every other thread I've been reading lately.
Seriously....I know that, at the very least, the CSL's OE fitment are Pilot Cup Sports which are cut slicks. IIRC the OE Fitment for the Evo are Yokohama AO48's which are again about as slick as you can get for the road.
I full well know the difference between slicks and road tyres.
Seriously BBT, grow the **** up and if you have a problem with me, add me to your ignore list because you're becoming nothing more than a troll..
Sorry to go off topic in relation to your post, Yaeger:
I was talking about tread, or rather the lack of it, when I was saying "what are basically cut slicks"
As agreed in an earlier post road tyres have to work over a wide range of temperatures and conditions.Ignore, deleted for sake of thread quality...
No way, your dodgy snotgobbler rants provide me a great deal of amusement - I don't want to miss out on that
Nah I call bullshit and backpedaling at an incredible rate. I must issue credit where it's due though, you're the most glib fellow I've ever seen on the forum. See, you said it in the context of why the tire got chewed up... unless you really think it was because of it's tread pattern (in which case you're stupid, not just lying)
Wow, how many multi-quote arguments am I in? 
Then sit back and enjoy. If you aren't involved, how about you don't chip in?
Glad you think that way. Standard road tyres can get chewed up as well, unless of course I am not understanding your meaning.
No they're not hand cut. I have watched World Rally thankyou very much I know how a cut slick comes about. I know why and when you use them. I don't need a lecture on things I already know. Perhaps I could have explained myself more clearly.
I know they are Road Tyres.. or else they would not be on the road, no? They still require heat to work and do not tend to fair well in wet conditions, they're trackday tyres.
Ok mate of course I don't.
Then either put me on your ignore list or STFU.
Sorry I muddled two letters up? Sheesh we all make mistakes. I don't moan at you because you can't use "you're" correctly.
I do have a problem with expressing my points in a clear manner. I have a genuine reason for this but it's not like you either a) need to know or b) would believe me.
It's much easier to say "basically cut slicks" than to say "high performance trackday spec tyres that are designed to be used hard and stay consistent at higher temperature ranges while still remaining legal for road use and having a half arse attempt in the cold and the wet.
Then sit back and enjoy. If you aren't involved, how about you don't chip in?
Glad you think that way. Standard road tyres can get chewed up as well, unless of course I am not understanding your meaning.
No they're not hand cut. I have watched World Rally thankyou very much I know how a cut slick comes about. I know why and when you use them. I don't need a lecture on things I already know. Perhaps I could have explained myself more clearly.
I know they are Road Tyres.. or else they would not be on the road, no? They still require heat to work and do not tend to fair well in wet conditions, they're trackday tyres.
Ok mate of course I don't.
Then either put me on your ignore list or STFU.
Sorry I muddled two letters up? Sheesh we all make mistakes. I don't moan at you because you can't use "you're" correctly.
I do have a problem with expressing my points in a clear manner. I have a genuine reason for this but it's not like you either a) need to know or b) would believe me.
It's much easier to say "basically cut slicks" than to say "high performance trackday spec tyres that are designed to be used hard and stay consistent at higher temperature ranges while still remaining legal for road use and having a half arse attempt in the cold and the wet.
So then you're just lazy, and by extention horribly inaccurate. The former means nothing like the latter.
Then you get on a tirade because you say ignorant things but it's never "what you really mean". Spend more time thinking, and less posting, and maybe you'll have a productive conversation someday. Verbosity for the sake of it is nothing more than handwaving.
I just like to give ****s like you something to laugh about.
Really? That's your whole motivation? I'm honored!
Ignore, deleted for sake of thread quality...
How about getting back to topic..
Indeed, I wish that one slide around a corner in a FOX didn't ruin my tyres for the next 4 laps and knock at least 3 seconds off my laptime
Well strangely enough I like to thank the people that posted in that thread as it genuinely helped. If it matters to you I'm back with my girl and we're happier than ever, and I'm also getting along with my Mum muuch better. Don't have a job but hey, I'm on the dole! Go me.
Was that supposed to mean anything?
Please don't ruin this thread. It was such a nice read untill the middle of the last page.
If you think the attached tyre (which is the one on the CSL) is a cut slick then you shouldn't really be in this debate.
No, they're actually A-046s which are much different to A-048s.
As said it was a poor way of explaining, which I have rectified in a post above.
My mistake..
Perhaps one of the big differences to real life vs LFS is that tyres in rl reach an operating temp (depending on how aggressive the driver is weather or not that temp is coolish, in the optimum range or abit hot) and are then quite stable with a slight cooling off as the tread wears down.
Were what we currently see in LFS can be a trend where temps keep esculating instead of stabalizing once the have reached a certain level. This could simply be due to the yet incomplete simulation of tyre wear and damage under aggressive driving conditions. i.e. when driving at the limit the surface of the tyre should be getting quite hot but in this state it will also be experiencing rapid wear - if this were to happen in LFS that could mean a reduction in transfer of heat from the surface of the tyre to the inner core of the tyre.
This would then mean that a greater portion of the core temp would be generated by molecular exitment of the rubber rather than by heat transfer causing the tyres to take longer to heat at the core and also to be more stable at operating temp.
It apears to me that alot of the grip loss experienced in rl is caused by a change in tyre chemistry (i.e. flex, softness - characteristics in general) of the tyre over it's life span, equally if not more grip is lost by wear of the tyre (i.e. graining, chunking etc) having an impact on contact patch area. Not so much by temperature as in LFS as these other issues are far more pronounced and have impact long before temperature can have the sort of imact as it does in LFS.
amp88 could you please post one more lot of data for perhaps the M3 as that appears to have been a better handling car with more consistent runs and even tyre wear just for comparison? Don't be lazy
Were what we currently see in LFS can be a trend where temps keep esculating instead of stabalizing once the have reached a certain level. This could simply be due to the yet incomplete simulation of tyre wear and damage under aggressive driving conditions. i.e. when driving at the limit the surface of the tyre should be getting quite hot but in this state it will also be experiencing rapid wear - if this were to happen in LFS that could mean a reduction in transfer of heat from the surface of the tyre to the inner core of the tyre.
This would then mean that a greater portion of the core temp would be generated by molecular exitment of the rubber rather than by heat transfer causing the tyres to take longer to heat at the core and also to be more stable at operating temp.
It apears to me that alot of the grip loss experienced in rl is caused by a change in tyre chemistry (i.e. flex, softness - characteristics in general) of the tyre over it's life span, equally if not more grip is lost by wear of the tyre (i.e. graining, chunking etc) having an impact on contact patch area. Not so much by temperature as in LFS as these other issues are far more pronounced and have impact long before temperature can have the sort of imact as it does in LFS.
amp88 could you please post one more lot of data for perhaps the M3 as that appears to have been a better handling car with more consistent runs and even tyre wear just for comparison? Don't be lazy
yeah its a whole 1.8% (ie practically nothing)
thats well within any margin of error especially with that degree of mechanical degradation on the tyres making any claims that the lap times were caused by heat completely irrelevant guesswork
and those typical curves are pretty useless and generally speaking any curve that claims to be typical especially in a books thats titled "speed secrets" instead of say "mechanics of tyres" is about as scientifically relevant as drawing two axes on the doodles of a 4 year old
and that best motoring test seems to confirm my suspicions that a tyre will disintegrated well before it can reach 150°C
I does cool down, but only after a good bit of driving. anyone who has done a enduro knows what I'm talking about. After lot of laps you have to work hard to keep the tires warm.
Yeah Glenn had me really pondering there for a bit...
But I think that means that his idea that you quoted is even more right; since less "core" material makes it more difficult to maintain temps in LFS. The molecular activity should remain relatively the same despite how much tread is left, but since heat dissipates more rapidly when there is less tread in LFS that would indicate that much of the core temp is related to therodynamic transfer from & to the surface rather than hystereis.
That or I've consumed too much Guinness; either of which is entirely possible. And it's only Wednesday, just imagine Friday.
Any professional driver, as claimed were driving these cars, should be able to keep their lap times within a couple of 10ths on a track that short. Looking at it from that standpoint, that's a huge degradation of the times.
There's a lot we don't know about that test. Thanks for pointing that out to all of us. But you make the assumption that the degradation happened prior to the last lap and that the degradation wasn't a result of cooking the tires (which it probably was).
I've seen that kind of degradation on tires. It usually happens after multiple track days and most often to front wheel drive cars. If you look at the pictures, it sure looks to me like the tire was rolling very far onto the sidewall indicating it had the pressure set too low for what they were doing. That will also cause degradation of the tire pretty quickly. But again, that's just a guess given the pictures and data that we have.
The elephant in the living room (Tire Physics)
(245 posts, started )
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