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Discussion Starter · #1 ·
I know I'm a boring old [expletive deleted] always whinging about my tyres, but I need a bit of guidance here.

After my initial wussy concerns about scrubbing out tyres at TD04, I've actually done so much travel recently that they're nearly due for replacement anyway - not helped by doing nearly 1000 miles after hitting a pothole in Scotland that put the tracking out slightly


Current tread depths vary from about 2mm (N/S/F) to about 4mm (O/S/R), all are legal but a bit scrubbed on the outer shoulder (usual story for me/my car) with meaty bits remaining on the inner edges. I'll rotate them front to back so the lowest tread is on the rear, but given some of them are very worn (<1mm)on the outer edge, do you think I'll get away with them for Anglesey? Not worried about killing them now, so long as they get me home after, just worried they might go too far? I'm a born worrier...


FWIW I've just picked up a spare alloy (unused, £50, result
) fitted with a part worn Falken, about 3mm so I can swap the worst-worn for that if necessary, though would probably fit to rear to keep matching pair on front.
 

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Dunno about Angelsey, and you don't specify what make of tyres you have AFAICS. This latter is very important, since softer tyres will obviously wear out quicker. You won't catch me using Pirellis on a (hot) trackday. They slide all over the place .
Everybody's driving on a track is different, but I would hazard a guess that 2mm is pushing it somehow. Especially if you want to make it home on those tyres afterwards (which I doubt
). Don't forget that you are going to be running on average about 10PSI above standard pressure on trackday (well, you should be!), and caning it round bends etc at speeds not normally reserved for road use. This will eat out more rubber, and quicker. Add to that the tyre temperature build-up during those runs, and even more rubber is going to be left behing on the tarmac.
If I was in your shoes, I would be looking for a complete set of tyres with some more rubber. Last thing you want to happen to you is that you run out of rubber by the end of the morning session .
 

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Discussion Starter · #4 ·
Stanley, I have conti sport contacts, which are moderately hard-wearing, and on the road run 2-3psi higher than minimum recommended to reduce wear on outer edge. For sure I'd be going to the max recommended pressure for the track.

Hmm, not going to invest in a new set before the day, that would be madness. Might try to find a part worn pair for the front... Any other views?
 

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I'd recommend you change the tyres. If it rains you'll be putting your car at risk with only 2mm (especially at the back).

Change the tyres for something good.

I bought 4 yokohama AVS sports for the 9-3. And gently scrubbed them in over the last week. I don't expect much wear on them if I look after the tyre pressures during the day.

p.s. The AVS sports are an awesome tyre. Quiet and very grippy in the dry and equally good in the wet... but still comfortable... I'm very pleased with them.
 

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Al - I had similar situation to you. My front Dunlops were down to 2mm. I decided to fit new ones in time for trackday.

Last year I had new Dunlops which had been on for 1,500 miles. Anglesey was wet, grip was great and tyres still looked new at end of day. I think grip would have been atrocious had they been worn to 2mm.

Get new (or newer) tyres with more tread. If Anglesey is wet your tyres will not wear noticeably - but if you have worn tyres you will have limited grip.
 

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Discussion Starter · #7 ·
Agree if it's wet then a new set would be most sensible, I'll have to keep an eye on the forecast. But if it's dry, I'd rather have worn/scrubbed tyres. It's not for nothing that production racers scrub half the tread off new tyres before using 'em!

The things is, if I get a new set before hand, I know the way this thing chews front tyres in the dry. Once you've established a pattern of tread wear on a new tyre, it continues to wear in that pattern - often becoming more extreme, so I'll end up with a nice new set that will last about 5 minutes...
 

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Originally posted by fliptop (9-5 V6 AgaPower):
[qb]Agree if it's wet then a new set would be most sensible, I'll have to keep an eye on the forecast.  But if it's dry, I'd rather have worn/scrubbed tyres.  It's not for nothing that production racers scrub half the tread off new tyres before using 'em!

The things is, if I get a new set before hand, I know the way this thing chews front tyres in the dry.  Once you've established a pattern of tread wear on a new tyre, it continues to wear in that pattern - often becoming more extreme, so I'll end up with a nice new set that will last about 5 minutes... [/qb][/b]
Which is why I say you should buy them now and scrub them in gently from now to the day.

You'll probably do upwards to a thousand miles between now and then???
 

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Tyre wear is inevitable - but remember that Anglesey has a proper surface, not a harsh abrasive surface that will easily chew tyres.

Let's suppose the following:
<ul type="square">
[*]Anglesey is 1.057 miles long
[*]Each session lasts 20 minutes
[*]You have seven sessions in the day
[*]You lap the track every one and a quarter minutes (75 seconds)
[/list]

If my maths is correct, then

<ul type="square">
[*]You will travel 112 laps
[*]You will travel 117.26 miles
[*]You will be tired at the end of the day
[*]You will have a perma-grin
[/list]

So, around 120 miles of spirited driving. It's going to depend a great deal on the type of tyre, the nature of your driving, the vehicle, the surface, and the weather.

So what does this prove? I'm not entirely sure other than my maths might be flakey.
 

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Tyres that are too new can actually wear quicker on a track day due to block twist. 3-4mm should see you OK for the day though. I would buy two new, good quality tyres (pref W, X or Z rated)and put them on the back, replacing the two most worn ones. More tread on the back is better in the wet, and won't hurt in the dry either.

You can keep an eye on wear during the day, and if you're tearing up the fronts, then you can swap them to the back to save tread.
 

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Discussion Starter · #11 ·
I think that might be the best compromise, Mark, "good thinking Batman"


Can't dispute your maths, John (though your assumption of me managing a 75 sec lap may be optimistic ) but I reckon I've seen noticeable wear on mine (again, just the outer shoulder) on a single journey when really pressing on (probably too much, but there you go...)

I think what all this is telling me is that when I bought the car I should have invested in some decent suspension to reduce roll & give the tyres more of a fighting chance. Not worth it for 12 months or so now...


Thanks to all for your thoughts and brain power
 

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 but I reckon I've seen noticeable wear on mine (again, just the outer shoulder) on a single journey when really pressing on (probably too much, but there you go...)  [/b]
Errrr..., outer shoulder you said? I don't have a 9-5, but that sort of wear in that location would have me worried. Can someone explain if this is "normal" on a 9-5?
 

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Discussion Starter · #13 ·
Certainly seems normal on my 9-5... Basically it's the outer edge of the tread, which is always going to be the bit that cops it the worst, isn't it? Even with the reinforced tyres I have now, you get a lot of sidewall flex under load, and on an understeery car like this that load is pretty high on the outer front tyre! Nothing to worry about AFAIK
 

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I'm buying a pair of tyres and I have a spare set of 16 x 6" wheels to put them on. My rear tyres have loads of life left, so I'll probably swap my old tyres around during the day and put the spare wheels on (if required) for the journey home.
 

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Hi Al,
It might have been due to the wet weather lubricating the surface, but last year my tyres didn't suffer much at all during the day. IF it's dry this year I'd be happier with your current tyres than brand new ones. But then again I'd have an eye to the forecast...

Nick.
 

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Well I'm taking 8 tyres,

2 new (7.5mm)
2 1/3 worn (5.5 mm)
2 2/3 worn (3.5mm)
2 very worn (1.5mm).

Depending on weather I will fit the top middle or bottom pairing (sort of wet, intermediate and dry )

The 2 extremes here:


 

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I will be taking my elvington "Baldies"
and buying some tyre softener (if its dry !!)
otherwise it will be the set thats on

goodyear fi's with about 5k miles on
and the pishelli ones on the back (hardly worn)
 

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I'll take my spare set of 17's too. Two are part worn (4mm ish) Pirelli Zero Neros, the others are virtually new Bridgestones. I may switch to these if it is wet or I'm not getting enough traction on the 18's...
 

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Discussion Starter · #20 ·
Just picked up a bootful of scrubbed tyres I scrounged from Haymill today (v. helpful chaps they are too
) - 2 x conti sport contact 2 and 2 x Pzero rosso
, all are at 2-3mm but more evenly worn across the tread than my current set - ie they have some meat left on outer edge. Tomorrow is crunch day, if the forecast suggests rain I get a new set of 4 (local ATS keeping them in stock for me for next week anyhow, more v. helpful chaps
); if it stays as is I pick the best 4 of what I have, get any that need it fitted, and head off to Chester at dark o'clock thursday morning
 
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