Michelin PS4 on 340i Touring

[Roma101]

Hi

I have the 18" M sport alloys with factory run flats (225 45 18 Y91 front and 255 40 18 Y95 rear).

I am sticking to the same size tyres for the new PS4 tyres. In respect of the load and speed ratings though, the PS4 tyres, according to the Michelin website, come in 91W or 95ZR(Y) (for the front) and 99 ZR(Y) (for the rears).

A numpty question, but does it matter that the load and speed ratings are slightly different than original spec.? Have people gone for 95ZR(Y) on the front or the 91Ws?

Also, Michelin say the spec of the PS4 tyres is 'XL'. What does that mean?

Thanks

[Smuler]

Roma101 said:

Hi

I have the 18" M sport alloys with factory run flats (225 45 18 Y91 front and 255 40 18 Y95 rear).

I am sticking to the same size tyres for the new PS4 tyres. In respect of the load and speed ratings though, the PS4 tyres, according to the Michelin website, come in 91W or 95ZR(Y) (for the front) and 99 ZR(Y) (for the rears).

A numpty question, but does it matter that the load and speed ratings are slightly different than original spec.? Have people gone for 95ZR(Y) on the front or the 91Ws?

Also, Michelin say the spec of the PS4 tyres is 'XL'. What does that mean?

Thanks

No, it's fine, the only requirement I've heard of is , for simplicity, captured here,

Although not illegal, it is not advisable to have tyres with a lower speed rating or load index than the manufacturer recommended tyre specification for your vehicle.

The ZR is cos it's adapted for higher speeds, no bad thing and XL is extra load and can run higher pressure which I think some performance car tires run at.
Your basically having a higher performance tire.

Anyway, I had PS4s on my 335i and they were excellent. I just went to my usual tyre fitter (trusted) and never paid much attention to those numbers

Michelin are helpful, feed in your registration and they'll confirm what's good or ask your trusted tyre fitter if you have one.

[Roma101]

Smuler said:

No, it's fine, the only requirement I've heard of is , for simplicity, captured here,

Although not illegal, it is not advisable to have tyres with a lower speed rating or load index than the manufacturer recommended tyre specification for your vehicle.

The ZR is cos it's adapted for higher speeds, no bad thing and XL is extra load and can run higher pressure which I think some performance car tires run at.
Your basically having a higher performance tire.

Anyway, I had PS4s on my 335i and they were excellent. I just went to my usual tyre fitter (trusted) and never paid much attention to those numbers

Michelin are helpful, feed in your registration and they'll confirm what's good or ask your trusted tyre fitter if you have one.

Hi. Thanks. I do and they have just confirmed they ordered the higher rated tyres anyway - 95ZR(Y) fronts and 99ZR(Y) rears.

Will get them fitted next week and I'll feed back on first impressions.

[VerySideways]

Roma101 said:

Hi. Thanks. I do and they have just confirmed they ordered the higher rated tyres anyway - 95ZR(Y) fronts and 99ZR(Y) rears.

Will get them fitted next week and I'll feed back on first impressions.

Going from runflat to PS4 you'd lose a little turn in feel because the runflat sidewalls are so stiff - by going for the XL (higher load rating) version on the fronts you'll mitigate that to a large degree.

I'm on the 19's so went from runflat to PS4S. I very much doubt you'll regret your decision

[SebringMan]

Another happy PS4 customer here .

I've tried both the PS4 and PS4S. The S does have the edge but the PS4 is a superb tyre nonetheless ; far better than the PS3 it replaced and IMHO better than the MPSS in the wet.

[Wills2]

I have PS4S on my M3, tremendous rear end grip but the front is a bit soft despite a higher load index rating on the front tyres than the star rated CSC5P it came with.

[Roma101]

Right. Had them fitted and the tyre shop did a good job and a good deal.

I have only driven back from the tyre shop (c. 15 miles), so these thoughts are very much first impressions and subject to the tyres "bedding in" properly. Although the guy in the tyre shop said Michelin are the only tyre manufacturer who have a process to skim off the very top layer once the production process is finished to drastically reduce this bedding in period.

The Michelins are more comfortable and smoother over broken / harsh tarmac than my Conti RFs. Therefore cracks in the road are noticeably less intrusive through the car. Road noise is also reduced on the Michelins. On the down side, as has been mentioned before, the car does feel a little bit more wallow-y (sp?) and a bit more barge-like. However, I'll put this down to being brand new tyres and the strange weather we had yesterday in the south (it hadn't rained much, but the roads were damp/greasy and didn't dry out). Also, the drive home was gentle, in Comfort.

So overall, I have seen some comfort benefits already, but it is too early to determine the performance benefits. Will have to report back in due course.

Do love the smell of fresh rubber though!

[Mike335i]

I'm about to fit my second set of PS4 rears. Grip is tremendous on them, as is traction, but I do seem to have worn through a set rather quickly.....

[mikeyscott]

I’m planning on fitting these on my 135i, but 225/255 to replace MPSS if I keep the car.

Wanting an auto as a manual as a daily...