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Discussion Starter #1 (Edited)
I've got a set of Pirelli Winter 240 Sottozero N1s mounted on Sport Edition Cup 4 Silver wheels purchased as a set for my 2008 Cayman S (non-PCCB.)

I didn't do much highway driving last winter, but this year I'm doing more and have the dreaded hand massaging steering wheel at speeds above 60 MPH.

So far, in addition to the road force balance they got at Tire Rack when new, this season I've had them spin balanced twice at two different shops and road force balanced once, with minimal changes to the problem. It's a bit reduced now but still there.

The tire shop checked for run out radially and linearly when doing the road force balance on the 9700 and found nothing out of spec, but are wondering if hubcentric rings are available or needed for these wheels as they suspect they're not centering on the hubs properly and causing run out that way.

Note that switching back to my summer tires on the Porsche front wheels makes the problem go away completely.

I'm wondering if there's a solution short of having to pay $$$$ for a set of Porsche wheels for winter use.

Yes the wheels are properly torqued and the pressure has been reset each time they've been rebalanced.

No mods to the car at all - I just want to be able to drive on my winter tires without feeling like I'm causing 20,000 of steering parts wear or that I'm prematurely wearing my pricy winter tires.

Unfortunately it appears no one has been able to get this issue solved in the other steering vibration threads I've found. :(
 

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Not quiet sure that i understand. Where did you get the rims? From tire rack with the tires? Yes wheel need ot be hub centric and cannot just be attached by the lugs. Big issues with spacers bigger than the OEM 5mm. They need to have a hub ring on them because if the spacer is bigger than 5mm and flush the lip is not giving enough support to the wheel. but i am not usre I understand that you would have a wheel that is made and fits the bolt pattern would not be made to sit on the hub ring. Doesn't make sense.
 

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Discussion Starter #3
I got a reply from Tire Rack that said the wheels in question do not need hub centric rings.

The winter setup was purchased as a wheel/tire combo from Tire Rack.

I didn't do much highway driving on them last winter, so though I had a very slight vibration last season, it didn't seem worth worrying about.

On my first drive after putting them on this year, the vibration was bad enough that I thought I had thrown a weight, so I had them rebalanced. That seemed to reduce, but not eliminate the vibration, so I had them spun again at a different shop, and the vibration stayed minimal but still there.

I had them road force balanced and that's when they checked the run out, and they said they were good, at least on the car.

I'm going to see if I can find anyone that can check on-car run out to see if perhaps one or both front wheels is defective, but it's getting pricy. (Still cheaper than OEM Porsche wheels, though.)
 

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I have the same wheels from Tire Rack, but with Blizzaks on them. I sometimes have a slight vibration in the morning when I leave the house, but it goes away within the first couple of miles (it's from the tires flat-spotting).

Maybe your tires have a slight defect, and it's not the wheels?
 

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Discussion Starter #5
The vibration remains for up to two hours (at least that's the longest highway drive I've made with them.)

The multiple shops doing the balancing and run out checks haven't noticed any flat spots.

I'm going to try to give a different shop with a Hunter 9700 a try this afternoon and see if they have any better luck with the RF balance...
 

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Good luck. Hope they can solve the problem.

Maybe it's not a flat spot, but a manufacturer defect in the tire? Maybe you want to contact Jim at Tire Rack to discuss replacement of the front tires with another set? See what his thoughts are....
 

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Discussion Starter #7
Looks like it is the tires.

Hunter road force readings:

L/F: 26 lbs
R/F: 24 lbs
L/R: 12 lbs
R/R: 10 lbs

Anything over 26 is a "fail" for the tire.

I've contacted Tire Rack to see if this makes them worthy of being replaced under warranty or if they're fine as long as they're right AT 26 lbs. of force.
 

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Discussion Starter #8
Follow Up:

Tire Rack is stepping up to the plate, as always, and we're going to warranty out my two front tires that generated excessive road force with two new ones given they still have 9/32" of tread left.

So a new set of 235/40R18 Pirelli 240 Sottozero Serie II N1s are on their way and should be here by Wednesday!

The biggest thing I've learned, other than that Tire Rack are great guys, is that (as usual) tools like Hunter 9700 road force balancers are only as good as the person running them.

One shop said everything was good, but it was the second shop that noticed the road force of the front wheels was way out of whack and borderline just plain defective…
 

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Follow Up:

Tire Rack is stepping up to the plate, as always, and we're going to warranty out my two front tires that generated excessive road force with two new ones given they still have 9/32" of tread left.

So a new set of 235/40R18 Pirelli 240 Sottozero Serie II N1s are on their way and should be here by Wednesday!

The biggest thing I've learned, other than that Tire Rack are great guys, is that (as usual) tools like Hunter 9700 road force balancers are only as good as the person running them.

One shop said everything was good, but it was the second shop that noticed the road force of the front wheels was way out of whack and borderline just plain defective…
Glad you found it, bummer having to waste time, effort and energy to figure it out. Seems like you almost always have to seek out a second opinion for one reason or another......:cheers:
 

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Discussion Starter #10 (Edited)
Crud.

Now it's back as bad as ever after putting perhaps 900 miles on the new fronts, and it seems to be worse when the temps are colder (shake was bad the other night when it was 18 degrees out, not so bad last night when it was 32.)

Note that if I put my OEM summer wheels/tires back on the front as a test, the vibration goes away completely.

Any ideas as to what to do now? I can't imagine they would need to be road force balanced again (this would be for the third time), and I wouldn't think tires would just "go bad."

I'll ping Tire Rack again but honestly, I suspect it's just something I'll need to live with every winter until they wear out unless anyone here has other ideas. :(

(Note - Tire Rack has been great about all this, but I have no proof at this time of where this problem lies, aside from the fact that it's in the front winter tires/wheels.)
 

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I've got a set of Pirelli Winter 240 Sottozero N1s mounted on Sport Edition Cup 4 Silver wheels purchased as a set for my 2008 Cayman S (non-PCCB.)

I didn't do much highway driving last winter, but this year I'm doing more and have the dreaded hand massaging steering wheel at speeds above 60 MPH.

So far, in addition to the road force balance they got at Tire Rack when new, this season I've had them spin balanced twice at two different shops and road force balanced once, with minimal changes to the problem. It's a bit reduced now but still there.

The tire shop checked for run out radially and linearly when doing the road force balance on the 9700 and found nothing out of spec, but are wondering if hubcentric rings are available or needed for these wheels as they suspect they're not centering on the hubs properly and causing run out that way.

Note that switching back to my summer tires on the Porsche front wheels makes the problem go away completely.

I'm wondering if there's a solution short of having to pay $$$$ for a set of Porsche wheels for winter use.

Yes the wheels are properly torqued and the pressure has been reset each time they've been rebalanced.

No mods to the car at all - I just want to be able to drive on my winter tires without feeling like I'm causing 20,000 of steering parts wear or that I'm prematurely wearing my pricy winter tires.

Unfortunately it appears no one has been able to get this issue solved in the other steering vibration threads I've found. :(
I am 90% certain I know the problem and can be rectified with the following process.

First let me share my own experience with you to establish the basis for my theory.

I have the same tires. Purchased new from a Porsche dealer already installed and balanced on the rims. I used it 1 winter. This winter I find the tires very susceptible to flat spotting. I drive for 30 minutes the hand massaging stops and the ride becomes smooth. If I drive the car every day the flat spotting is not as bad and goes away sooner.

Here is the theory: if you have got the tires balanced with the flat spots, you will be good until the flat spots disappear after a lengthy drive, then you are back to vibrating wheel since the balancing is no longer any good.

Here is the fix: fill your tires 50psi leave overnight. Following day drive for a lengthy period with the 50psi. do not need to go over 60mph. Go for a 30 minute ride. Then drop your wheel pressure to 30/37 regular pressure. Go for another ride for 30 minutes over 60 mph. Then go immediately in for a road force balancing while the tires are hot, round and with no flat spots. Even a 1 hour wait for balancing may flat spot the tires again. So I recommend to set up an appointment with a shop ready to accept you so you can go on the lifts as you drive in. Once balanced, you problem should be gone. Note that, after a lengthy park the flat spots will return and require a 30 minute tire warm up before they disappear.

Good luck.
 

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Discussion Starter #12
Thanks, I'll give that a shot.

Flat spotting seems like a good analysis given that I do tend to notice it more after it's been sitting all day at work compared to when I'm doing a lot of running around.

That having been said, it also doesn't disappear after a multi-hour highway drive. :(
 

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I have used two different sets of the Pirelli 240 Sottozero N1's (currently have the Serie II) and have never experienced flatspotting, even when the car has been sitting for up to two weeks.
 

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Discussion Starter #14
Not to resurrect this thread from the dead, but I'm currently pondering the purchase of a set of Cayman 18" wheels from Wheel Enhancement, as I was never able to eliminate the vibration. I'm almost 100% sure it's the Sport Cup 4S wheels, but I can't prove it, and so I can't really get Tire Rack involved.

I had them road force balanced four different times and always had vibration, which went away immediately when I put my summer tires/wheels back on for the season.
 

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Interesting problem. Assuming the diameter of your new tire is the same as your old tire, you should be able to swap out one new wheel at a time with one OEM wheel to determine which wheel is the culprit. The other thing I'd test is driving without the center cap. It might be coincidence, but (during the tire swap), I left my center cap off and my problem went away. The center cap never really sat right so I then swapped that center cap with one in the back with no issues so far.

I would be curious about the results of the wheel swap if you can do it.

Good luck and keep us updated!
-Moto
 

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I wasn't involved with this one but if anyone ever has a problem just let me know. When you place the order enter my name on the order as a contact and if anything is going on customer service should let me know.
 

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I'm interested to run across this thread in searching. I bought the Sport Edition wheels and had some old R comps put on them, and the vibration was terrible above 65 mph. I haven't had them rebalanced because it's just not worth it and it could well be the tires, but...


I also have a set of Sport Edition wheels (obviously a different style) that I use to run winter tires on my M3, and I have never been able to get them balanced right. I've had them redone 3 or 4 times, but the vibration is still there. With a string of weights that look like the anchor on the Titanic I've gotten it to the point where it is barely tolerable.

In the fool me once, fool me twice vein, I'm not going to buy another set of Sport Edition wheels. You don't always get what you pay for, but sometimes you do get what you don't pay for.
 
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