Tyres going out of shape new?

[DickP]

Hi

I replaced the Michelin Pilot Sport 3 on my car with Michelin Primacy 4 and the car gets intermittent vibration at speed. I have had this before with tyres going oval once speed picks up. Is anyone aware of a defective batch of Primacy 4? Pilot Sport 3 were fantastic but was hoping for slightly quieter tyres with less rolling resistance and improved mpg, seem to have just got tyres that randomly generate vibration on motorway at over £600 for the set

(Tyres have been rebalanced as well to no avail)

[swisstoni]

Do these tyres have some noise deadening feature perhaps?

On another brand I had the misfortune to use, there was a foam ring inside the tyre.
If this came loose, you had the fun of an intermittent wheel imbalance.

[DickP]

Unfortunately I have no idea. Usual place I used to get tyres is in a different part of the country so was starting afresh finding a tyre fitter locally that seemed to be good, but was not permitted in the workshop when they were fitting tyres to the wheels so never saw inside the new tyres.

The Primacy 4 tyres are a year old before fitting though having checked the date on them. Circa halfway through last year is the manufacturing week and year.

How do I go about rejecting? I have read that it looks like I'll have to stump up another several hundred pounds to get other tyres (i.e. anotehr set of PS3) fitted and hope the ones I've taken off are found defective? If not, that's going to be around £1,200 I'm down??! Can it be a bad combination of suspension spring rate etc. with soft sidewalls of the tyre? Car is mk3 Superb estate SE L Executive.

[swisstoni]

I’d go in on the presumption that they are defective and make this the tyre shop’s problem.

The problem appeared with the new tyres did it not?

[DickP]

Yes problem only appeared with the new tyres. Think I’ve done near 1k miles on them now hoping it was them needing to break in. It’s only properly noticeable on the super smooth new tarmac sections of motorway, put it on the old rough surface motorway sections and the road surface masks the problem to a large extent!

How does it work with tyres and consumer rights? I need to have the car for work purposes as do big miles as part of the job. Ie resolution needed asap as don’t have the time to go chasing round try this or that etc.

[swisstoni]

If they find the defect, presumably you’d be able to live with the defective tyre(s) whilst they obtained new ones.

If they can’t find the defect then perhaps get a second opinion from another tyre place. The places that do race car suspension setup are very good but aren’t on every street corner admittedly.

I’ll let someone more qualified comment on the consumer rights aspects.

[DickP]

The tyres would have to be sent away to be checked though surely? So I would have a car without tyres unless I got some more??

[Scrump]

I would be surprised if all 4 were defective (although could be a bad batch).
Have you tried swapping the fronts to the rear and vice versa to see if that makes a noticeable difference? (I presume you are feeling this vibration through the steering wheel).

[swisstoni]

DickP said:

The tyres would have to be sent away to be checked though surely? So I would have a car without tyres unless I got some more??

I’d hope that they could spot the problem without being sent away.
If that was going to have to happen then they ought to arrange temporary replacement I would have thought. Most people have one spare at best.

[DickP]

Thanks for the replies. Issue is felt in both front and rear of car, ie wheel and body. Not necessarily at the same time. As mentioned last time I had this was tyre going oval but also could be bad combination of tyre and car suspension I guess??

Will call tyre fitter and see what happens but can’t imagine it’s going to be cheap as I doubt there is much profit in tyre fitting.

[DickP]

So tyre fitter helpful but limited as the order was through Black Circles, who were willing to send to garage for independent assessment. However after a few more miles the vibration seems to be dissipating. I guess it might have been a releasing compound layer giving the vibration before?

What I do notice now is that the car jiggles and bounces on imperfections across the motorway, particularly where the motorway surface is rippled (e.g. lane 1) or rutted. On Pilot Sport 3 it never did this.

Do tyres take time to soften the sidewall after being brand new and unused?

Could the softer tyres be conflicting with the soft suspension of my car?

Tyre pressures are as per car's book.

[swisstoni]

New tyres should feel better than the old ones if anything.
Never had this issue normally. They don’t need ‘breaking in’ like shoes.

[E-bmw]

DickP said:

Tyre pressures are as per car's book.

Checked with what, as it does sound like pressures are high.

[Pica-Pica]

swisstoni said:

New tyres should feel better than the old ones if anything.
Never had this issue normally. They don’t need ‘breaking in’ like shoes.

Even shoes don’t need ‘breaking in’.

[Smint]

Lots of tyres need bedding in, which more correctly means scrubbing the chemical residue from the mould off the treads.

This could be the issue here, but no harm in lifting one wheel at a time and spinning it by hand, you'll soon see if anything is out of shape, tyre or wheel.
Pay close attention to the bead area, if there wasn't enough lube applied to the bead it's not unknown for a tyre not be fully seated.

One other thought, are the wheels aftermarket, do they have spigot ring adaptors fitted (usually hard plastic compound rings that allow an oversized wheel centre to fit the hob snugly), if even one of those has been lost the wheel won't centre by wheelbolts alone.

We're assuming new tyre sizes, including aspect ratio, are correct and any aftermarket wheels have the correct offset.

[E-bmw]

Pica-Pica said:

swisstoni said:

New tyres should feel better than the old ones if anything.
Never had this issue normally. They don’t need ‘breaking in’ like shoes.

Even shoes don’t need ‘breaking in’.

That's what he said.

[ninjag]

Try Road Force Balancing, it should be able to tell you if the tyre if not true and sometimes it can be fixed with the machine as well.

[Pica-Pica]

E-bmw said:

Pica-Pica said:

swisstoni said:

New tyres should feel better than the old ones if anything.
Never had this issue normally. They don’t need ‘breaking in’ like shoes.

Even shoes don’t need ‘breaking in’.

That's what he said.

No.

[swisstoni]

Pica-Pica said:

E-bmw said:

Pica-Pica said:

swisstoni said:

New tyres should feel better than the old ones if anything.
Never had this issue normally. They don’t need ‘breaking in’ like shoes.

Even shoes don’t need ‘breaking in’.

That's what he said.

No.

I don't think shoes need breaking in normally either. Nevertheless the notion that they can be broken in exists.
Which is why I used this as a handy analogy for the suggestion that these tyres will improve with wear.
Hope this helps.

[GreenV8S]

swisstoni said:

New tyres should feel better than the old ones if anything.
Never had this issue normally. They don’t need ‘breaking in’ like shoes.

Depends what you're doing with them, but there are several types of 'breaking in' that will change the behaviour of tyres.

Many new tyres are sold contaminated with release agents which will make them very slippery for the first few hundred yards.

Tyres that are put under heavy load repeatedly will wear the tread blocks so that they are flat when the tyre has distorted under that load. This tends to improve grip under those conditions, although it can make it worse under other conditions. This wouldn't normally apply to road tyres.

The rubber that the tyres are made from is vulcanised but still relatively soft. As the tyre is put through heat cycles it will continue to harden.

Tyres that have new full tread blocks will distort more under load than tyres with less tread. The softness of the new rubber exacerbates this. Road tyres used for motorsport may even be ground down deliberately to benefit from the softer rubber compound of brand new tyres without all the associated tread distortion.