Michelin PSS - Tracking - Unstable

[Simon_M]

Ahh, you filled with nitrogen? That will be why.

 

[supaer]

What is the exact difference in psi here? Between single occupant and being four up with luggage?

Got to say I've never ever had the problems the OP has and if in doubt (with any vehicle) I go with 40psi. Surely the tolerances aren't that fine?

Difference in PSI was quite a bit from what I remember. AM not with the car so cant check this atm

 

[-Ian]

Ahh, you filled with nitrogen? That will be why.

As a side note I've read so many threads with people saying they get more mpg etc because they paid extra to have their tyres inflated with nitrogen.......

Biggest hyped up marketing ploy ever when you consider that normal air is 78% nitrogen to start with.

I've worked in the aviation industry for 25+ years and we use 100% nitrogen in aircraft tyres for these reasons.

It stops corrosion of mag alloy wheels plus there is no chance water vapour within the tyres freezing with the massive temperature changes, anything from plus 40 to minus 60 in very short space of time. There is also no chance of an explosion if there is a blowout within the wheel well on take off.

So basically save your money and don't be fobbed off with the bull**** because replacing 78% nitrogen / 21% Oxygen / 1% other gases with 100% Nitrogen is not going to make any difference at all with day to day driving.

 

[G.P]

Surely the tolerances aren't that fine?

Well yes they can be, for instance if you run recommended (road use) pressures around a track your tyres will become over inflated quite quick.

Normal pavement use and 2psi can mean over the life of a tyre it won't wear even across it's width.

Why would they make soft sidewalls that give the feeling of unstableness.

Softer walls proved less noise and more comfort, can also use slightly thinner materials within costing less to manufacture. That said there are also many downsides..

 

[supaer]

i didnt pay extra for nitrogen it is just part of the deal. I didnt even get a choice in the matter.

I am going to change the pressures this week and hopefully this will cure it, as i cant stand to drive all the way down to italy and back on these tyres like this!!

Looks like i am going to have to go back to the conti's

 

[BIRMA]

i didnt pay extra for nitrogen it is just part of the deal. I didnt even get a choice in the matter.

I am going to change the pressures this week and hopefully this will cure it, as i cant stand to drive all the way down to italy and back on these tyres like this!!

Looks like i am going to have to go back to the conti's

Good excuse to put a few miles on the tyres though.

 

[supaer]

yeah if its really rubbish on the way down ill burn the rears and buy some contis from mercedes.....

just make sure i check there in stock first lol.

 

[BIRMA]

yeah if its really rubbish on the way down ill burn the rears and buy some contis from mercedes.....

just make sure i check there in stock first lol.

I would give them time because everyone I know who drives a high performance car enthusiastically rates them very highly.

 

[Mrhanky]

Difference between low and high load psi levels can be quite large. Iirc on mine it's 35 - 44 psi.

I run mine at 39 psi as I find it turns better and the tyres last longer with less dreaded inside wear.

 

[supaer]

So I dropped the PSI to 44 and 42 cant remember which I did on the front and rears. The ride has defo improved and is softer.
BUT
the problem is still there and I have run the tyres for about 250 miles now and the only thing which. I just want to be more specific so if anyone can offer any more advice I would be grateful.
Speeds between 80-90 if there is a slight bump in the road or dip the steering wheel feels a bit loose and quite light. I have read posts on here about previous issues like mine but I am not near to those speeds. The steering wheel rocks in my hands when this happens and does not feel firm.
Comparing this to my Golf on the motorway when this happens (Golf R has PSS also) it feels a lot firmer. I am pretty sure when I had the Conti's it didn't feel like this.

Tracking has been done, although going back to wheels in motion as the steering wheel is not 100% straight, although I don't think this could affect it. They adjusted the front toe angle and replaced the tyres, other than that nothing else.

Any more ideas from anyone? CHeers

 

[camerafodder]

Those pressures sound high to me. What does it say in the manual or on the inside of the fuel filler flap?

 

[supaer]

Those pressures sound high to me. What does it say in the manual or on the inside of the fuel filler flap?

Those are the pressures it says inside the fuel cap for 19 inch wheels 2 passengers and 2 bags.

 

[C240Sport97]

I have run the tyres for about 250 miles now

give it another 500 miles

 

[supaer]

give it another 500 miles

Really? Surely they cant take up to 750 - 1k miles to get sorted?!

 

[C240Sport97]

Really? Surely they cant take up to 750 - 1k miles to get sorted?!

either that or replace them all now ...

 

[supaer]

either that or replace them all now ...

I don't think they are faulty lol

 

[BIRMA]

I don't think they are faulty lol

I don't think they can be faulty having put them on two cars so far and immediately thinking I've ruined the handling/ride on the first car I just dialled in this factor with the second car. Although I drive my cars with the single person occupancy tyre pressures. With my Phaeton now its a sheer bliss when you get a move on on a decent A road.

 

[supaer]

I don't think they can be faulty having put them on two cars so far and immediately thinking I've ruined the handling/ride on the first car I just dialled in this factor with the second car. Although I drive my cars with the single person occupancy tyre pressures. With my Phaeton now its a sheer bliss when you get a move on on a decent A road.

So you just kind of go with it and accept that's how they are?!

 

[BIRMA]

So you just kind of go with it and accept that's how they are?!

Initially I think so, have you tried the lower tyre pressures for single person occupancy?

 

[Moosey]

Yup I fitted new tyres to the back of my car. F1 Asymetric 2's. 275/30/19

When driving home I thought I'd made a massive mistake as the car was all over the place . Now 1,000 miles and 1mm of tread wear later they are performing fabulously well

I'm not disagreeing per sae but on my old Megane R26, when I fitted Eagle Asymetrics, I noticed an immediate improvement in grip and turn in. Granted it was a FWD machine so not squirmy under power and the previous tyres (that came on the car when I bought it) were Falken's and not in the same league but the difference even before sealing agents had been worn away etc was night and day.