Tyre quality ?

Express Andy · Post by **Express Andy** » Mon Oct 08, 2018 9:43 am

Hi has any one run Kumho PS91 tyres the car I bought has a brand new set on. I would rather have original Michelinâ€™s as this is surely what the car was designed to run on? How would I know if there runflats ?
Cheers guys any help much appreciated

Bob · Post by **Bob** » Mon Oct 08, 2018 10:15 am

I've no experience of those tyres, but you should easily tell if they are runflats, just look for the RFT marking somewhere on the carcass.

FYI, you car should not have runflats as standard. That is one of the key changes that Alpina made over the BMW base spec.

Fast3000 · Post by **Fast3000** » Mon Oct 08, 2018 12:27 pm

Mine was also on some random budget brand when i got the car. They looked quite new with plenty of tread.
Had all 4 swapped for Michelin PS4. I wouldnt say the difference was obvious straight away but after a few more miles on they are most definetley a better tyre!!

Express Andy · Post by **Express Andy** » Mon Oct 08, 2018 1:51 pm

Thanks chaps still lot to learn about Alpina and the changes they made over standard many thanks, does any one have a list of the changes on the d3 Biturbo over bmw normal spec ? It would be use full, Iâ€™m sorry if Iâ€™m going over old ground.

ChrisLux · Post by **ChrisLux** » Mon Oct 08, 2018 2:06 pm

On a side-note, Kumho tyres are actually good tyres, but are normally more associated with 'hot' hatches, they are standard on the new VW Polo and they were standard fitment for some Minis, but actually also some 3 series

http://www.tirebusiness.com/article/201 ... oe-fitment

But I can understand not wanting them on Alpina, I wouldn't either

Express Andy · Post by **Express Andy** » Mon Oct 08, 2018 3:30 pm

Thanks for the link I have read some very good reports on them and seem a good tyre on the whole. I ran the Bridgestone re 070 on a sti Subaru which is the Oem tyre I believe Subaru and bridge stone worked very closely to develop the correct tyre for the car I was thinking did bmw / Alpina do the same ? Iit was a great tyre really suite the car and itâ€™s handling but shocking on the limit in the wet great dry tyre.

---pete--- · Post by **---pete---** » Wed Oct 10, 2018 10:21 am

I've actually put Khumo tyres on both my Alpina's on the last change.

I was recommended them and if you check the grading of them, they perform exactly the same in Wet Handling and Fuel Efficiency as the Pilot Sport 2 and only a slight increase in road noise. given the significant price difference I thought it was worth a go and I'm not disappointed at all.

Obviously the Michelin is the tyres recommended but I still have to ask myself whether we are really just paying for the name rather than a real world clear difference in performance. For me, this time around, I went with the 50% price reduction and 98% same performance option.

Post by **Charles** » Wed Oct 10, 2018 11:27 am

---pete--- wrote:Obviously the Michelin is the tyres recommended but I still have to ask myself whether we are really just paying for the name rather than a real world clear difference in performance. For me, this time around, I went with the 50% price reduction and 98% same performance option.

It may no longer be the case but, in the past, ALPINA have tested with Michelin and incorporated the specific sidewall softness of Michelin rubber into their suspension calculations to get the exact feel they are looking for.

Bob · Post by **Bob** » Wed Oct 10, 2018 4:51 pm

Charles wrote:
---pete--- wrote:Obviously the Michelin is the tyres recommended but I still have to ask myself whether we are really just paying for the name rather than a real world clear difference in performance. For me, this time around, I went with the 50% price reduction and 98% same performance option.
It may no longer be the case but, in the past, ALPINA have tested with Michelin and incorporated the specific sidewall softness of Michelin rubber into their suspension calculations to get the exact feel they are looking for.

You have to admire the attention to detail but I do wonder how much difference a layman, driving on our potholed highways and byways, in a car with â€œxâ€ years of suspension component wear would notice. I suspect, everything else being â€˜factoryâ€™, on another brand of same spec tyres would make only a marginal difference.

ali · Post by **ali** » Wed Oct 10, 2018 9:17 pm

Tyres are the only area that connects the car to the road.
An area never to be compromised in my humble opinion.

Bob · Post by **Bob** » Wed Oct 10, 2018 9:59 pm

ali wrote:Tyres are the only area that connects the car to the road.
An area never to be compromised in my humble opinion.

Don't get me wrong, I feel the same, so I'm not suggesting a set of Nankang Ditchfinders or the like, but another premium brand/BMW OE option such as Pirelli or Dunlop.

It was the optimised suspension set up, specifically designed around the sidewall stiffness of a Michelin tyre that i was questioning.

Post by **Charles** » Thu Oct 11, 2018 9:06 am

CaesarBob wrote:
ali wrote:Tyres are the only area that connects the car to the road.
An area never to be compromised in my humble opinion.
Don't get me wrong, I feel the same, so I'm not suggesting a set of Nankang Ditchfinders or the like, but another premium brand/BMW OE option such as Pirelli or Dunlop.

It was the optimised suspension set up, specifically designed around the sidewall stiffness of a Michelin tyre that i was questioning.

A fair few years ago I was swayed to replace a worn out set of Pilot Sports with Pirelli rubber, on the back of the Autocar Tyre test at the time - which was carried out using an E46 330i. 250 miles later I fitted a new set of PS tyres because the ride on the Pirellis was dreadful. Specifically, the way the car turned in felt completely wrong - too stiff and no progressive give to allow me to "lean" on the tyres in the turn. Now I am not a tyre engineer but it was clear to me that the tyre construction was playing a major part in this.

When I discussed this with the ALPINA Ops Director at the time - a certain Kris Odwarka of this parish - he explained about the detailed work they did with Michelin and how tyrewall flex was a key part of the suspension ride and feel. He also explained about the high speed testing they did because, unlike their Munich cousins, ALPINAs weren't speed-limited.

I don't doubt that other tyre brands are able to match the sticker performance of Michelins and even offer a price advantage, but that ignores the part that Michelin tyre construction plays in the whole ALPINA feel.

Bob · Post by **Bob** » Thu Oct 11, 2018 10:45 am

Really interesting to hear that the difference was so noticeable.

Metrics · Post by **Metrics** » Wed Oct 17, 2018 11:50 am

I'm with Charles on this one, however I will raise one small detail - the tyres the cars were developed with are not the tyres now fitted when buying new. For example early 2000 Alpina had the original Pilot Sport. Certainly my V8S did as evidenced by the spare - but I'm now running 4S. Even my D5 had Pilot SuperSport - also now running 4S.
PSS > 4S have a different carcass construction. So it won't be exactly like for like compared to the originals - but in my mind Michelin have a formula/DNA and are unlikely to digress massively from it and it's a well proven track and solid reputation that I'm buying into.

Going back to the point raised by Charles, Alpina are certainly specific and detailed with their chassis tuning. A simple example of this is spring rates which are tailored to the car and the specific options it has (due to weight).