Track day tyre conditions

Parapara2017

I'm taking my car to the track for a morning session next week, recently changed from 245/30/20 to 255/35/20. The 255 are new and primarily daily driving duties don't want to trash them on the track ideally.

Have the set of 245s but one of them is fairly worn. There was uneven tyre wear on the inside of all the tyres which has now been fixed so this one is at the wear indicator on the inside and maybe 1mm off it in the middle and outside.

It's a morning session reckon it would survive / be ok? The other option is I have a 245 with plenty of tread but a sidewall tear which is fairly big but unsure if it's structural enough, especially for track duties if under a lot of pressure. Any thoughts?


https://i.imgur.com/TIrysPi.jpg
https://i.imgur.com/AavWVBQ.jpg
https://i.imgur.com/LSYZ6iW.jpg
https://i.imgur.com/7YCIIx3.jpg
https://i.imgur.com/vCVyifp.jpg
https://i.imgur.com/Nl8na2b.jpg
https://i.imgur.com/R8dmveD.jpg

zilog_jones

They all look fit for the bin...

Midnight_EG

Get rid, sidewall damage is a massive concern and you have flatspotting all over the tyre too.

mickdw

For a trackday, the tyres near the wear limit are 100 percent. You wouldn't want anything better if using road tyres really.

Pops_20

Those tyres look well past anything I would ever have on my car. Bin them.

Parapara2017

For clarity that's just the one tyre for tread wear, different angles. The other thread are all grand for tread life plenty of meat.

Sidewall rip is also a separate tyre.

mickdw

Did people even read that it's for a trackday. Yes, you don't want tyres that are going to blow out but I see nothing wrong with tyres near wear limit.
Personally I'd invest in a second set of wheels with track tyres. They will give you more grip in the dry at least and will stand up to the track use better.

Parapara2017

mickdw wrote: »

Did people even read that it's for a trackday. Yes, you don't want tyres that are going to blow out but I see nothing wrong with tyres near wear limit.
Personally I'd invest in a second set of wheels with track tyres. They will give you more grip in the dry at least and will stand up to the track use better.

Yeah plan to maybe get a cheap set of 18s over the next year so I don't have to keep swapping tyres on and off my current wheels but not atm, this is a bandaid fix for it last track day till next season I'd say

Parapara2017

Tyre shop reckon the sidewall tear wasn't a big deal not structural so using that instead of the more worn one.

mickdw

You going this Monday?
Hope to be at July one myself

Parapara2017

mickdw wrote: »

You going this Monday?
Hope to be at July one myself

Yeah Monday morning session

Wailin

What type of cars are most common at these track days lads? Hot hatches, M cars etc?

Parapara2017

Wailin wrote: »

What type of cars are most common at these track days lads? Hot hatches, M cars etc?

Mix, mostly track ready cars like stripped fiestas and other stock cars, some regular road cars like M cars or hot hatches.

That was my experience last time anyway

Wailin

Any daysuls?

mickdw

Wailin wrote: »

What type of cars are most common at these track days lads? Hot hatches, M cars etc?

Everything and anything. stripped civics and celicas are about the best cars around the track at trackdays. Lots of fiestas, lotus elise, bmw e36, e46, m cars, all sorts.
From my experience, the expensive stuff is only there for show and doing 4 or 5 laps and to be fair, it would get mad expensive to heavily track a recent M3 for example from brakes to tyres, normal repairs and the danger of doing crash damage.

mickdw

Wailin wrote: »

Any daysuls?

You will see the occasional one.

Paddy@CIRL

Wait, your logic is that since you're going to be pushing your car at decent speeds, you should chance using heavily part worn or damaged tyres? You need better tyres on track, not ones that are barely hanging in there.

corkgsxr

Paddy@CIRL wrote: »

Wait, your logic is that since you're going to be pushing your car at decent speeds, you should chance using heavily part worn or damaged tyres? You need better tyres on track, not ones that are barely hanging in there.

Mental. On motorbikes we throw away track tires that look fine but the grip has went away a touch

gk5000

If its dry then thread does not matter, and in fact slows you down hence why race cars use slicks....no thread at all.

Parapara2017

Yeah was grand my tyres had enough life just that one that was a problem put the other one on as it was grand.

Tyres worked great and infact improved as the morning went on it felt like (even after warming up)

Great morning out tyres served me well might have lasted the full day 😂

corkgsxr

gk5000 wrote: »

If its dry then thread does not matter, and in fact slows you down hence why race cars use slicks....no thread at all.

It comes down to alot of stuff, pressure compounds etc.

Alot of tires fall off after 60% wear regardless of type. It's to do with heat control and dissipation in the tire.

A thinner tire will flex and build up heat faster but still struggle to hold it. You end up colder or hotter than you need.

punisher5112

LIGHTNING wrote: »

Well that's massively wrong on so many fronts, I don't know where to start

I laughed;-)

corkgsxr

Going doing trackday during the week. Hope the local garage has a load of wanked tires I can take for some proper pace.

mickdw

Parapara2017 wrote: »

Yeah was grand my tyres had enough life just that one that was a problem put the other one on as it was grand.

Tyres worked great and infact improved as the morning went on it felt like (even after warming up)

Great morning out tyres served me well might have lasted the full day 😂

Of course they were fine.
It's not like you were looking to gain fractions in a competitive event. If doing serious track work, track tyres will be needed but imo it would be foolish to do a trackday on a new 600 to 800 quid set of road tyres.

gk5000

LIGHTNING wrote: »

Well that's massively wrong on so many fronts, I don't know where to start

Curious, why?
Its the rubber that grips, not the gaps/threads which only act to channel water if needed.

zilog_jones

LIGHTNING wrote: »

Well that's massively wrong on so many fronts, I don't know where to start

I know where to start: Tyres have "tread" not "thread", they're not made out of string.

Tacitus Kilgore

gk5000 wrote: »

Curious, why?
Its the rubber that grips, not the gaps/threads which only act to channel water if needed.

You forgot about the extra added traction on dry tarmac from the steel wires poking out of the tyres too.

gk5000

LIGHTNING wrote: »

On a tyre that has treads when you get down to the point where they are "slicks" you have used all useful friction material. At that stage you a driving on the structure of the tyre which will be poor to say the least. In the same way when a slick tyre wears out its useable material its of no use (check out Delamination videos online).

Plenty of race cars use grooved tyres, F1 did it for a very long time. In fact practically all the race cars I have driven have used grooved tyres.

Ok, but there is a layer of wear rubber on the worn tyre before it starts into the structure rubber or wire.
Knew a guy years ago who went to Skip Barber racing school in USA. They used to let the school wear down Eagle GT's and then use them on races (probably not super competitive). The idea was that the compound was good and this was a cheaper way of getting a reasonable slick tyre.


Separately, the grooves were originally introduced to F1 bout 25 years ago to slow them down.

mickdw

LIGHTNING wrote: »

gk5000 wrote: »

If its dry then thread does not matter, and in fact slows you down hence why race cars use slicks....no thread at all.

On a tyre that has treads when you get down to the point where they are "slicks" you have used all useful friction material. At that stage you a driving on the structure of the tyre which will be poor to say the least. In the same way when a slick tyre wears out its useable material its of no use (check out Delamination videos online).

Plenty of race cars use grooved tyres, F1 did it for a very long time. In fact practically all the race cars I have driven have used grooved tyres.

To be fair the f1 grooves were to hold them back. Also there was a time in f1 where some compounds would start to come back to the driver when the grooves wore out although that was the exception.

gk5000

Well maybe don't quote me on the Skip Barber fully - maybe it was just to let the school wear them in a bit as opposed to fully down to slicks, but this was many many years ago.
Guy I knew hooked up with a lady who had just bought a Porche 9?4 auto, which included a free weekend at the racing school, but she could not drive manual so he went.

Yes on the F1 records, but imagine if they hadn't added the grooves where it would have been.

mickdw

LIGHTNING wrote: »

gk5000 wrote: »

Ok, but there is a layer of wear rubber on the worn tyre before it starts into the structure rubber or wire.
Knew a guy years ago who went to Skip Barber racing school in USA. They used to let the school wear down Eagle GT's and then use them on races (probably not super competitive). The idea was that the compound was good and this was a cheaper way of getting a reasonable slick tyre.


Separately, the grooves were originally introduced to F1 bout 25 years ago to slow them down.

Working at a race school if I ever went to another professionally run operation (which Skip Barber is most definitely) and I saw road tyres that were down to slick levels I'd be walking away. If your down to slick levels you are taking a big gamble. I have had a tyre failure on a race track before and it wasn't pleasant.

A set of slicks for a modest size or even a set of decent track tyres isn't that expensive. They set I got for my race car was less than what I'd pay for decent road tyres.

Also there are still some standing records on existing F1 tracks from the grooved tyre era so slowing them down didn't work so well

Well it actually did.
Following Senna and Ratzenburger deaths and a whole host of big accidents, there were rule changes to slow things down. The cars were narrowed by 200mm which is a serious revision plus grooved harder compound tyres were brought in. Times were significantly slower but after a couple of seasons, the Engineers had clawed back all the time. That begs the question - what times would they have been doing if left to old rules?