Tyre compounds

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Miztaziggy
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Location: Tadcaster

Tyre compounds

Post by Miztaziggy »

Last week I bought some Diablo Supercorsa race scrubs for track days this year.
If anyone's interested by the way, look up trumpet tyres on facebook. Turns out he lives just down the road from me, he has a massive stock. He sells half decent tyres suitable for road (maybe done 20 laps) for £80 a pair. He sells good quality ones that have only done 2 or 3 laps for £100 a pair and these are suitable for track use up to fast group. They also do slicks and race wets for a good price if anyone's interested.

Anyway, I got chatting to him, he knows his stuff and looks after the tyres of the racers he's getting these from.

I've always thought that the Diablo Supercorsa was like a Metzeler Racetec and that you'd run a medium rear and soft front, for grip and longevity combination.

He said that was totally wrong, and most riders run a softer tyre on the back rather than the front for a couple of reasons.
1 - the soft compound heats up and also cools down more quickly. The front has much more air flow, and a soft front tyre will cool down too quickly on track.
2 - the softer tyre on the rear apparently lasts longer than the medium tyre.

He also tells me that the soft compound is better for a hot track. That does match what Pirelli's own chart shows, SC0 being softest and SC1 being harder:

REAR TYRE
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FRONT TYRE
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The tyres he sells are both SC1 front and rear.

I'm struggling to understand how a softer tyre works better at hotter temperatures. I thought a softer tyre would heat up more and become too soft in the heat.

Or, is it that a soft tyre just needs more heat in it to work, and a harder compound tyre doesn't?

I imagine that when a soft compound tyre gets hot, it wears quite quickly, but he tells me it doesn't wear as fast as a harder tyre....


And most confusing of all, why is it reversed for the front tyre?
It seems that on the rear, the soft compound better for hot, smooth tracks, but on the front, the harder of the 2 compounds is better for the hot smooth tracks.

:wtf: :wtf: :wtf: :wtf: :wtf:
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lumpyv
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Re: Tyre compounds

Post by lumpyv »

I reckon you would be better off asking the tyre geezer all these questions.

:confused :confused
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Miztaziggy
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Re: Tyre compounds

Post by Miztaziggy »

lumpyv wrote:I reckon you would be better off asking the tyre geezer all these questions.

:confused :confused
I did, he confused me, and started to waffle a bit....
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lumpyv
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Re: Tyre compounds

Post by lumpyv »

oic ? somebody must know ?
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Kev L
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Re: Tyre compounds

Post by Kev L »

James Whitham was doing a piece to camera on Sunday about the different options available from Pirelli and said how counter intuitive the softer tyre working on a hot track it is.
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Miztaziggy
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Location: Tadcaster

Re: Tyre compounds

Post by Miztaziggy »

Kev L wrote:James Whitham was doing a piece to camera on Sunday about the different options available from Pirelli and said how counter intuitive the softer tyre working on a hot track it is.
Interesting....

It does seem totally counter intuitive to me, why you would run soft rear, hard front, and get less wear on a soft than on a hard....
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nt1980
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Re: Tyre compounds

Post by nt1980 »

On a hot track the surface can become very greasy a bit like riding on a damp track is the best i can explain so you would use softer rubber for this as said above the was a good explanation on the bsb about tyres
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