Where's my tyre tread gone?
Discussion
Been out in the Spyder today and found it a bit tail happy but put it down to the damp roads.
When I got home I checked the rear tyres and both of them have worn out the central band of tread to a smooth finish!
The pressures are always as Porsche state and they've done 7300 miles.
Tyres are Pirelli P Zero (I know, I know....but the car came with them!)
Is this just normal wear, because I thought middle tread wear indicates over-inflation which they aren't.
When I got home I checked the rear tyres and both of them have worn out the central band of tread to a smooth finish!
The pressures are always as Porsche state and they've done 7300 miles.
Tyres are Pirelli P Zero (I know, I know....but the car came with them!)
Is this just normal wear, because I thought middle tread wear indicates over-inflation which they aren't.
Old Trout said:
So is that 14,600 altogether?
I had the same issue on my 6GT3 - they seemed fine then suddenly very worn in the middle. No obvious reason.
If I type it again it'll be 21900.I had the same issue on my 6GT3 - they seemed fine then suddenly very worn in the middle. No obvious reason.
Bit of a bugger when the rest of the tyre's fine
Looks like new ones needed then, and under inflate them...
2 E46 M3s - both doing a pair of rear tyres around 3500 miles.
C4S doing 12k to a pair of rears. First ones were biased to wearing the centre band out, I run slightly lower pressures now and get reasonably even wear.
I'd expect your car (lighter weight, quality suspension) to be relatively light on its tyres assuming its not being driven with the tail out everywhere.
C4S doing 12k to a pair of rears. First ones were biased to wearing the centre band out, I run slightly lower pressures now and get reasonably even wear.
I'd expect your car (lighter weight, quality suspension) to be relatively light on its tyres assuming its not being driven with the tail out everywhere.
Zyp said:
Been out in the Spyder today and found it a bit tail happy but put it down to the damp roads.
When I got home I checked the rear tyres and both of them have worn out the central band of tread to a smooth finish!
The pressures are always as Porsche state and they've done 7300 miles.
Tyres are Pirelli P Zero (I know, I know....but the car came with them!)
Is this just normal wear, because I thought middle tread wear indicates over-inflation which they aren't.
These cars tend to wear the center of the tread more than the edges, when everything is aligned properly.When I got home I checked the rear tyres and both of them have worn out the central band of tread to a smooth finish!
The pressures are always as Porsche state and they've done 7300 miles.
Tyres are Pirelli P Zero (I know, I know....but the car came with them!)
Is this just normal wear, because I thought middle tread wear indicates over-inflation which they aren't.
At first I experimented with the tire pressures thinking they were too high then I went the other way thinking the tires were under inflated and growing at speed. Neither proved to be the case.
However, I will point out you have to be sure the tires are properly inflated. Be careful. Sometimes the tire inflation settings are given for a vehicle carrying its max. load in which case unless your car is carrying 2 adults and their luggage the tires will be over inflated and this can accelerate the tendency of the center of the tire to wear more than the edges.
(This happened with my 996 Turbo, was happening until a tech pointed out that the chart giving the tire inflation pressures was based upon the car's max. load weight which included 4 people (4-seater you know) and several hundred pounds of luggage. A few (2) psi drop in air pressure cut down on the center wear and the ride got a bit less harsh too.)
Pirellis are hyper-critical to correct pressures in my experience. Even running them 3-4 psi low made a noticeable difference to the handling of my Mk1 GT3, the equivalent Michelins would tolerate running 5 psi low without any problems.
Worth checking your tyre pressure gauge to make sure it's still accurate ? I ask, as used a good quality gauge ( a well known brand) thinking it's readings were gospel, it later transpired it was reading low by 6psi . . . . . .
Worth checking your tyre pressure gauge to make sure it's still accurate ? I ask, as used a good quality gauge ( a well known brand) thinking it's readings were gospel, it later transpired it was reading low by 6psi . . . . . .
Slippydiff said:
Pirellis are hyper-critical to correct pressures in my experience. Even running them 3-4 psi low made a noticeable difference to the handling of my Mk1 GT3, the equivalent Michelins would tolerate running 5 psi low without any problems.
Worth checking your tyre pressure gauge to make sure it's still accurate ? I ask, as used a good quality gauge ( a well known brand) thinking it's readings were gospel, it later transpired it was reading low by 6psi . . . . . .
My experience with Pirelli tires agrees with your hyper-critical comment. It was when I was experimenting with tire pressures that I created a vague tire out of balance like vibration in my Boxster which proved to be the Pirelli front tires overinflated by a few psi.Worth checking your tyre pressure gauge to make sure it's still accurate ? I ask, as used a good quality gauge ( a well known brand) thinking it's readings were gospel, it later transpired it was reading low by 6psi . . . . . .
Slippydiff said:
.....Worth checking your tyre pressure gauge to make sure it's still accurate ? I ask, as used a good quality gauge ( a well known brand) thinking it's readings were gospel, it later transpired it was reading low by 6psi . . . . . .
This might qualify as "daft question of the day", but how do you test a tyre pressure gauge for accuracy? I've never heard of anyone offering a calibration service (or even anyone with a certified-accurate gauge to test against). If you just compare it to another off-the-shelf gauge, how do you know it's not a mile out too? Ian_UK1 said:
This might qualify as "daft question of the day", but how do you test a tyre pressure gauge for accuracy? I've never heard of anyone offering a calibration service (or even anyone with a certified-accurate gauge to test against). If you just compare it to another off-the-shelf gauge, how do you know it's not a mile out too?
A very fair point - I have three Porsche (badged) gauges and each shows a different reading and all disagree with what the tyres used to come from Byfleet inflated to. I would always get the car back, check the (cold) tyres and let air out until the pressures were per the book.One thing the OP could try is vast amounts of rear camber as this is guaranteed to wear out the inner edges long before the centres........
Ian_UK1 said:
This might qualify as "daft question of the day", but how do you test a tyre pressure gauge for accuracy? I've never heard of anyone offering a calibration service (or even anyone with a certified-accurate gauge to test against). If you just compare it to another off-the-shelf gauge, how do you know it's not a mile out too?
I've been using the same tyre supplier for the last 20 odd years, they're a small independant, they have a "master" gauge which is certified calibrated. They use it to check their workshop gauges weekly.I had new tyres fitted on the rear of my daily driver, they asked me what pressures I wanted in them, so I told them.
Once scrubbed in, I noticed that the grip wasn't what I'd expected, so I checked them with my gauge. My gauge indicated that they were running at 26psi cold (should have been 32psi) I rang the tyre fitters and told them they needed to get their gauges checked !
They corrected me, and said that contrary to my initial thoughts, it was my gauge that was at fault.
I duly went up to Demon Tweeks and bought a replacement (a bigger face and glycerine filled too) Sure enough when I came to use it, it read spot on 32psi. Exit stage left my old tyre pressure gauge . . . . . (the lack of grip was due to a step backwards in tyre spec, at my behest)
keep it lit said:
Nurburgsingh said:
If only the centres are worn then they have been overinflated.
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