My Michelin PS4S First Thoughts

[Junebug85]

Thread Revival!

Just recently picked up a 6 GC and it came with 20" Dunlop Sport Maxx GT tyres. First thing I noticed was that I could feel a slight vibration between 60 - 80 mph.... Wheels were balanced again but the vibration was still present.

I had 20" Pirelli Run Flats on a F10 before but they didn't have this issue. Maybe it's the Dunlop tyres

Will changing to MPS4s resolve or make a positive impact in regards to the vibration?!?!

Reading online, I've read that some have had the issue and it was drivetrain or Guibo related

Either way, i'm keen to ditch the Dunlops soon!

[arucano]

were the Dunlop's road force balanced. How many miles do you have on the car?

[Junebug85]

Originally Posted by arucano

were the Dunlop's road force balanced. How many miles do you have on the car?

No, just normal wheel balancing was done...

24,000 miles on the car with OEM 373M wheels

[JBF650]

Originally Posted by Junebug85

Thread Revival!

Just recently picked up a 6 GC and it came with 20" Dunlop Sport Maxx GT tyres. First thing I noticed was that I could feel a slight vibration between 60 - 80 mph.... Wheels were balanced again but the vibration was still present.

I had 20" Pirelli Run Flats on a F10 before but they didn't have this issue. Maybe it's the Dunlop tyres

Will changing to MPS4s resolve or make a positive impact in regards to the vibration?!?!

Reading online, I've read that some have had the issue and it was drivetrain or Guibo related

Either way, i'm keen to ditch the Dunlops soon!

Junebug85, I'm sure you know the answer to this hahahah. ditch those terrible bloody Dunlop RF's and go with the awesome Michelins Pilots P4s.. or something in this region.
I did after seeing / asking members and threads on here as well as asking for advice locally. I have not once regretted it, where I was avoiding even the smallest imperfection to save the crash and bump I no longer need to. I had vibration issues from 60-80 while not serious more annoying really... put it down to the bubble that was forming in the side wall of the front RT's. ( these were the original tyres my car came with, my car when I bought it was a very low klm vehicle used as an occasional 3rd car by the 2nd owner)
I said it before in my thread.... the very minute I drove out of the tyre centre when I changed to the Michelins I felt the smooth, soft quiet and vibration free difference. Traction with the Michelins is so superior to the RFT's I find myself driving like a kid in a dodgem at times.... before the rft would understeer and slip and were the only aspect I didn't enjoy on my 650...

give your 6er a xmas present as well as yourself!

[ezmaass]

Originally Posted by Junebug85

Thread Revival!

Just recently picked up a 6 GC and it came with 20" Dunlop Sport Maxx GT tyres. First thing I noticed was that I could feel a slight vibration between 60 - 80 mph.... Wheels were balanced again but the vibration was still present.

I had 20" Pirelli Run Flats on a F10 before but they didn't have this issue. Maybe it's the Dunlop tyres

Will changing to MPS4s resolve or make a positive impact in regards to the vibration?!?!

Reading online, I've read that some have had the issue and it was drivetrain or Guibo related

Either way, i'm keen to ditch the Dunlops soon!

A few thoughts:

I believe the Dunlop Sport Maxx GT is a summer tire only, correct? If so, and if you intend to drive the car during the winter (or just below freezing temps), you'd need to change them out anyway. Keep in mind that the Michelin Pilot Sport 4S is also a summer tire.

I switched my 650 to Michelin's A/S 3+ tires. They're an ultra high performance all-season tire - a relatively new category but essentially it's designed to give you 90% of what a max performance summer tire would do but with the versatility of all-season (some light snow duty), a slightly more comfortable / GT oriented ride, and longer tread life. Assuming you're not pushing the 6 to the limits of adhesion on any regular basis, and you'd like to keep from swapping tires between seasons, this could be a good option.

The Pilot Sport 4S is absolutely a great tire (I have them on my R8), they're just not nearly as forgiving (comfortable) as the A/S 3+ in my experience, and as mentioned above, the softer compound means they wear a lot quicker. These tires are well suited for very sporty summer driving, but I personally kept away from them on the 6 given that I don't use my 6 that way - it's a big, heavy car, so I'm not going canyon carving with it. And, in that case, the PS4S will just result in less comfort and quicker tread wear for no upside for me.

Now, regarding the vibration, you should have it properly diagnosed. Vibration can be anything from a drivetrain issue to a bent rim, or just a poorly balanced tire. You can eliminate one at a time, for sure. If you're going to replace the tires, I'd have the wheels checked for bends and corrected at the same time. I have the 19" OEMs on mine, and they were definitely prone to bending with the factory Goodyear RFTs. I had the same setup on my previous 550xi, and again, same problems.

While I like the look of larger rims, the road quality here in the Northeast US just isn't ideal for them. The 19's are bad enough, so I expect the 20's would be that much more difficult to maintain. I've found that BMW's OEM wheels do bend quite easily, though, and with it will introduce vibration.

[Junebug85]

Originally Posted by JBF650

Junebug85, I'm sure you know the answer to this hahahah. ditch those terrible bloody Dunlop RF's and go with the awesome Michelins Pilots P4s.. or something in this region.
I did after seeing / asking members and threads on here as well as asking for advice locally. I have not once regretted it, where I was avoiding even the smallest imperfection to save the crash and bump I no longer need to. I had vibration issues from 60-80 while not serious more annoying really... put it down to the bubble that was forming in the side wall of the front RT's. ( these were the original tyres my car came with, my car when I bought it was a very low klm vehicle used as an occasional 3rd car by the 2nd owner)
I said it before in my thread.... the very minute I drove out of the tyre centre when I changed to the Michelins I felt the smooth, soft quiet and vibration free difference. Traction with the Michelins is so superior to the RFT's I find myself driving like a kid in a dodgem at times.... before the rft would understeer and slip and were the only aspect I didn't enjoy on my 650...

give your 6er a xmas present as well as yourself!

Thanks for your reply mate.

The vibration issue is a weird one as it’s not there all the time. Before it was very much noticeable but after adjusting the tyre pressures to 2.6 and 2.8 bar, it went away. Yesterday driving home in the rain in comfort +, I felt the vibrations around 70 mph. This morning driving to work on the same road in comfort + and Sport – no issues!

Haha! I’m just waiting for the Michelin £100 off 4 tyres offer and then I will pounce on this!

Hope the new tyres will get rid of the issue and I can start to enjoy the car more!

[Junebug85]

Originally Posted by ezmaass

A few thoughts:

I believe the Dunlop Sport Maxx GT is a summer tire only, correct? If so, and if you intend to drive the car during the winter (or just below freezing temps), you'd need to change them out anyway. Keep in mind that the Michelin Pilot Sport 4S is also a summer tire.

I switched my 650 to Michelin's A/S 3+ tires. They're an ultra high performance all-season tire - a relatively new category but essentially it's designed to give you 90% of what a max performance summer tire would do but with the versatility of all-season (some light snow duty), a slightly more comfortable / GT oriented ride, and longer tread life. Assuming you're not pushing the 6 to the limits of adhesion on any regular basis, and you'd like to keep from swapping tires between seasons, this could be a good option.

The Pilot Sport 4S is absolutely a great tire (I have them on my R8), they're just not nearly as forgiving (comfortable) as the A/S 3+ in my experience, and as mentioned above, the softer compound means they wear a lot quicker. These tires are well suited for very sporty summer driving, but I personally kept away from them on the 6 given that I don't use my 6 that way - it's a big, heavy car, so I'm not going canyon carving with it. And, in that case, the PS4S will just result in less comfort and quicker tread wear for no upside for me.

Now, regarding the vibration, you should have it properly diagnosed. Vibration can be anything from a drivetrain issue to a bent rim, or just a poorly balanced tire. You can eliminate one at a time, for sure. If you're going to replace the tires, I'd have the wheels checked for bends and corrected at the same time. I have the 19" OEMs on mine, and they were definitely prone to bending with the factory Goodyear RFTs. I had the same setup on my previous 550xi, and again, same problems.

While I like the look of larger rims, the road quality here in the Northeast US just isn't ideal for them. The 19's are bad enough, so I expect the 20's would be that much more difficult to maintain. I've found that BMW's OEM wheels do bend quite easily, though, and with it will introduce vibration.

I appreciate your reply mate.

For the winter, I have a set of 18” alloys with Pirelli Sottozero Winter Tyres. It will be interesting to see if the car still suffers from the vibration issues, which seems to minimal now – as it happens now and again.

Bent rim – that could be a possibility I guess thinking about it. But like you said it can be checked when the tyres are changed. Are you saying you had the same vibration issue and bent rims were the cause?

The UK roads are not that much better! Constantly having to avoid craters and holes.

I'll look into the AS3+ Tyres. Thanks for the alternative recommendation.

[ezmaass]

Originally Posted by Junebug85

I appreciate your reply mate.

For the winter, I have a set of 18” alloys with Pirelli Sottozero Winter Tyres. It will be interesting to see if the car still suffers from the vibration issues, which seems to minimal now – as it happens now and again.

Bent rim – that could be a possibility I guess thinking about it. But like you said it can be checked when the tyres are changed. Are you saying you had the same vibration issue and bent rims were the cause?

The UK roads are not that much better! Constantly having to avoid craters and holes.

I'll look into the AS3+ Tyres. Thanks for the alternative recommendation.

Well, I can't say it's the same vibration you're experiencing, but yes, I had bends in the rims (3 of 4!) that definitely began causing vibration at highway speeds - typically once you hit that 60mph mark it would become much more obvious. My previous 550xi suffered from the same issue - exactly the same setup of rims and RFTs.

When I switched out the RFTs, I had the rims repaired, and everything has been fine since. So again, I can't say it's what you're seeing, but these RFTs are just known to bend rims - the carcass inside the tire is just so stiff (clearly to ride on it if air is lost) that any decent impact just seems to kill the rim. Yet another reason to dislike RFTs.