Pirelli P7's - WEIRD tyre wear

[caprinolaw]

I have Pirelli P7's on my Roc (18").

Anyone who is familiar with them will know they have 4 channels (the channels on which you base the tread depth).

I have now done 14,000 miles and on inspection of the two middle channels of the two front tyres I have noticed they are down to the limit (1.6mm), however the inside and outside channels of the tyre are at a good 3-4mm.

Is this something other people have experienced in a Roc?

I'm used to the outside channels wearing quicker than the inside but not the other way round!?

I've been very careful in keeping my tyre pressures correct and so am really puzzled by this.

I've drawn a (bad) illustration and very much exaggerated diagram to indicate what I mean.

tyre.gif

[Chungster]

that's caused by over inflation on the tyre pressure front mate to cause middle section wearing much faster than inside/outside sections.

it's interesting tho...the fuel cap suggest 19's be pumped to some silly pressure of 38 psi..yet the guys at National Tyres when putting on my new Contis..did them at 33psi, and that is according to the Continental Tyre Pressure chart they use!

And I knew my OE tyres (Dunlops) were at 33psi as well in the 15k miles i ran them for. So what's the Fuel Cap data all about?

[caprinolaw]

Thats the thing i just went based on the fuel cap less 2 psi.

Have just been down to kwik fit to get them done and they said that over inflation shouldnt have worn them as extremely as it did. Their explanation... I cane my car too hard.

...Not that I care, All of my tyres are free :-)

[RW1]

Yes, had it with Bridgestone Potenzas. Much quicker though, tyres would have been in your condition by 9,000 miles.

Its a characteristic of some wider tread width tyres. Due the construction, the tyre when running at speed and centrifugal forces, the tyre deforms outwards in the centre of the tread area. This leads to the increased tread wear you have got. Some brands are more prone than others.

I deflated my tyres to 30psi from the VW setting on the fuel tank flat of 33 psi. This appears to have arrested the some uneven wear in the centre but not all of it. Given measurements are not that accurate over a short mileage I've just done, I'd say that its only resulted in a 30% reduction of the wear effect of the outer edges to centre section ratio.

Bonus was the Scirocco is more planted on the road and less road noise. They still wear down pretty fast but across the whole tread face.

C.