Final Trackskills Track Day of 2019, Sunday 3rd November.

Mont

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Can anyone read tyres. Odd question I know, but I have some odd tyre wear on the front passenger side front tyre. I normally expect the outside edge to be worn ,but this is in from that. It is a Yokohama intermediate at 25psi cold. A friend who has more experience of Motorsport rubber reckons his does the same when pushed on.

@RubberLover might have an idea Des.
 

RubberLover

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@RubberLover might have an idea Des.
Hard to say from that photo and Iā€™ve next no near experience with track stuff but I would hazard a guess of overheating = overinflation at speed? Have you checked what the tyre pressure is immediately after putting in? Left front would get more abuse than right front.

Anyone with any other ideas?
 

svensktoppen

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Was thinking the same. Something to do with tyre pressure. Doesn't look like a geo problem.

The other possibility is curb damage. Especially considering you haven't seen this type of wear before.

Edit: Actually, since the damage is on the inside tyre (passenger side round Kirky), it's almost certainly curb damage (y)

22-23 psi cold is what I would run with the 750kg Lotus on track tyres (R888). Yours was the Leon right? It's about twice the weight. Might have gone too low. Certainly not too high at that :innocent:

Which Yokohamas are they? Look like AD08? That's more of a road tyre which is also great on track. They do have a stiff outer wall allowing them to be run at lower pressure, but not quite as stiff as the more track focussed 888 or A088. I go about 25psi cold with the Lotus on AD08.
 

Gibbo

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@jagged Had the M3 on the dyno outing interest to see what figures she is pulling, 302hp at 7000 is pretty good going for 22 years old.

FB_IMG_1573322589229.jpg
FB_IMG_1573322584442.jpg
 

Dieseldes

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Was thinking the same. Something to do with tyre pressure. Doesn't look like a geo problem.

The other possibility is curb damage. Especially considering you haven't seen this type of wear before.

Edit: Actually, since the damage is on the inside tyre (passenger side round Kirky), it's almost certainly curb damage (y)

22-23 psi cold is what I would run with the 750kg Lotus on track tyres (R888). Yours was the Leon right? It's about twice the weight. Might have gone too low. Certainly not too high at that :innocent:

Which Yokohamas are they? Look like AD08? That's more of a road tyre which is also great on track. They do have a stiff outer wall allowing them to be run at lower pressure, but not quite as stiff as the more track focussed 888 or A088. I go about 25psi cold with the Lotus on AD08.
Thanks for the advice guys. They are an odd ball Yokohama rallycross 054 tyre. Got a few sets at the right money so... I didn't look at pressure all day so next time might check that when they are warm.
@jagged Had the M3 on the dyno outing interest to see what figures she is pulling, 302hp at 7000 is pretty good going for 22 years old.

View attachment 256070View attachment 256071
What rolling road is that? Seems health enough, making power as rpm rises. Any scope to lift the limiter?
 

pablo

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302 probably isnt far off what it was putting out new, the evos were notorious for dynoing well under the claimed 321
 

jagged

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Tyres and how to make the best of them is a whole degree course on its own , so many variables , cold tyre pressures , hot pressures , track temp etc ,etc
At last Sunday's track day we ran cold temps of 27psi and had great grip when the track dried , tyres are pirelli dh slicks , ie.hard compound, rears have done approx 8 trackdays , fronts have done 4 days , and of course were used to start with !
Normally would run 23psi on warmer days ie 15 degrees ambient temp .
As stated it's a whole jigsaw of variables , but i think if a tyres destroyed then something is badly array , most trackers have destroyed the passenger front at kirkers , myself included brand new kumho too šŸ˜Ÿ
 

Cooper

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There was a guy in with me taking video footage and drone stuff in the paddock- did it ever appear online?
 

FM155

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Can anyone read tyres. Odd question I know, but I have some odd tyre wear on the front passenger side front tyre. I normally expect the outside edge to be worn ,but this is in from that. It is a Yokohama intermediate at 25psi cold. A friend who has more experience of Motorsport rubber reckons his does the same when pushed on.
As said by a few here, I'd also say over inflation at speed. If they are rallycross tyres, they will be a very soft compound so they will build heat very quickly and then the centre part of the tread will get mullered. On R888's, NS2R's and Toyo R1R's that I've used on the MX5 in the Targa Rallies, we use 22 cold which goes up to 24 or 26 depending on the day temp. I usually check the pressures after the first few tests after we have some temp in the tyres and usually would have to drop a few psi on the left rear due to doing 360's round pylons etc.
 

Gibbo

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Thanks for the advice guys. They are an odd ball Yokohama rallycross 054 tyre. Got a few sets at the right money so... I didn't look at pressure all day so next time might check that when they are warm.

What rolling road is that? Seems health enough, making power as rpm rises. Any scope to lift the limiter?

DP motors has it newly installed, gettingset up for 4wd soon too.

Standard is around 7600 rpm , I've seen ones with a 8500 limiter right enough.
 

jagged

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302 probably isnt far off what it was putting out new, the evos were notorious for dynoing well under the claimed 321

Happy enough with 300hp at 7k , engine was pulling strongly with still 700rpm to limiter.
Probably make 310 .
BMW figure of 321hp is made under ideal conditions using at least 100 ron petrol , so to get close to that with a 22yr old with 107k mls on standard engine with only mod being a decat , fuel was 4 parts 97 ron - 1part 115ron race fuel which we used for the first time at the last trackday ,should be 100ron ish .
Given that this engine has been 100% reliable over the last 6yrs of tracking ( 4k mls + ) l think i'll leave well enough alone
 
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