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Tyres

Tymmorgan

New member
Sorry guys.

Another question.

My 981 has 20" alloys on it with Pirelli tyres. When turning at slow speeds the front tyres seem to jump & slide. Is this normal?

Driving as normal road speeds they are fine just when manoeuvring at slow speeds
 
Yes this is normal, there is a name for this which escapes me at the moment.

I have heard that fitted with Michelin’s it does not do this so it must be something to do with Pirelli’s

 
Its pretty normal. Usually at its worst if you reverse with full lock in Winter with Summer tyres fitted. Its to do with the suspension geometry - all my Boxster have done the jerking in reverse on full lock

 
Hi

This is perfectly normal especially at this time of year. It's known as the Ackermann principle which you can research on the internet. It's because of the different steering angles from side to side. It is absolutely nothing to worry about though I know it sounds and feels horrible!

Enjoy your 981

[:D]

 
It's known as the Ackerman principle pretty normal with big tyres on full lock.

Don't think it's down to a specific brand of tyre does tend to get worse as the tyres age.

Hope that helps.

Cliff

 
On other cars (Audi in particular) I found it more pronounced on worn tyres. Went away (or less obvious) with new tyres

 
If I try helps, my 987.2 does it on old and new Bridgestones, damp surface, bit cold, esp reversing and very low speeds, all normal for this car design.

Other cars do the same, but not all, i.e. My Skoda Superb, wife's Citigroup and my 1973 911 are unaffected.

 
My cayman 981 did not do this with 20” wheels (aftermarket Tomason)and Goodyear F1 tyres. I switched to OZ 18” wheels with P Zero’s and have exactly the same “problem”. I am also glad to hear that it is nothing to worry about. I also have a perfect potentiometer accelerator box available. After getting a fault code a new one was fitted but the code still persists - seems like valve solenoids, two new ones been fitted early Jan. I hope that puts the light out?

 
Again the P Zero’s are harder or go hard, so the effect is very notable.

How this tyre can be N spec is Shocking. It's not fit for purpose.

 
I think a lot of the hate for P-Zeros is out of date. The latest P-Zero (PZ4) is acrually a very good tyre; in generic form it has acquitted itself very well in the last three EVO tyre tests, particularly showing itself to had better wet grip than the PS or PS4.

Now of course the N spec versions will be different, but frustratingly the tyre manufacturers rarely disclose how much they have changed the specification. Sometime they do, for example the BMW version of the PS4S has four different compound bands acroos the tread compared to only two on the generic version.

it used to be “accepted wisdom” that P-Zeros became much worse as the tread wore down. I’ve repeated this myself several times. I recently drove 1500 fairly hard miles in the Scottish Borders in a hired 718S shod with N1 P-Zero pz4 tyres worn down to 4mm and less - even in torrential rain they didn’t put a “foot” wrong.

Dont get me wrong, I would still prefer the PS4S N0 (despite these same tyres being responsible for a spin into a ditch which necessitated the said hire car)

The PS4S is a brilliant tyre. But the current P-Zero N1 is not that bad.

 
I have only driven 160 miles on these tyres, 18“ PZero, and have already decided they are not for me. Noisier than the 20” Eagle F1 tyres and little improvement in ride quality (why I changed from 20” to 18“ in the first place). They will be coming off as soon as the car comes out of winter hibernation and new Michelins going on. Perhaps these PZero‘s are good for track days - but little else. If anyone wishes to by 200 mile old 18“ P Zeros please ring 07748 657118 I will change sooner if anyone wants them.

 

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