UUronL

What does a staggered set up mean? Thanks
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530i sport with Dunlop runflats - no AS. The car has never tramlined - not even once. It tracks true and with no ambiguity.

I have driven it on perhaps the worst possible surface, grooved concrete - on I66W - west of the capitol beltway. No issues whatsoever.

alexnyc

What does a staggered set up mean? Thanks
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Staggered setup=your rear tires/rims are of different size than your fronts are,i.e it is what you get in a BMW sport package,on my 545 it is 245/40/18 front and 275/35/18 rear.
I am happy to report that my new Pirelli PZero Nero M+S is almost completely tramlining-free,much better ride, decent grip and perfect cornering(its still not broken in-i only have 50 miles on them-still have those small rubber hairs all over the tire and i feel it on hard acceleration/cornering)I wish i ve done it year ago!

Ågent99

I dunno, I have the F1s on my 2001 530i and it tramlines on a certain stretch of road just as much as my 545i with the rf dunlops. I always thought it was just a crappy road and somewhat wide, low-profile (read: stiffer) tires causing it but that was just a WAG.
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Hmm. Where is a tire engineer when you need one.
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I always thought tramlining was your tires following ruts in the road (as described above) so I wouldn't think the tires have anything to do with it. Heck, even my 1990 Toyota Pick-up tramlines on this certain stretch of road I take home from work everyday. Maybe we are mixing up terms and really describing two different problems?

HHP

Have any of you guys seen a link on this forum to talk about tires?
Specifically RF vs NRF and also the brands? Thanks

Mercy

my 545i with the rf dunlops were perfect (no tramline) until about 5000 miles when I started to notice. Now at 9000 miles they are terrrible. Worst tires ever.

Oh, and did I mention the noise. When new they were silent, now they compete with my truck.

UUronL

Just had another perfect opportunity to test... While driving to lunch I had to take a road where just over half the width had been freshly paved, creating a rut right where the driver's side wheels would track. The car didn't dart or pull or tramline. Tracked true and straight with no extra steering input. To confuse the hypothesis even more, my runflats are running lower pressures, not higher ones which someone suggested would help alleviate tramlining.

So we have four sets of conflicting assertions:


Dunlop RFTs tramline and others don't
Dunlop RFTs don't tramline and others do

Staggered wheel setups tramline
Staggered wheel setups don't tramline

AS correction can manifest as tramlining
AS correction cannot manifest as tramlining

High pressure can alleviate tramlining
Low pressure does not exhibit tramlining



I'm willing to say at this point that we haven't been able to deduce anything meaningful from this interaction.

Mercy

Has anyone tried it with no tires. Need to find out if its the car or the tires.

rodybmw

Actually I am glad to hear that AS has nothing to do with it, as I am a great proponent of AS.

I think that it still is at least partially a tire issue. As I mentioned above, in my past experience with other cars and tires I have been able to confirm that the tires were indeed the cause of the problem by switching tires (same size sport tires on the same car). I can remember at least two instances that this happened and in both cases it wasn't the old "worn" tires that gradually developed the tramlining problem, but instead the brand new tires that immediately upon purchase had the problem. Being the same size sport tires the only difference was the thread design. In both cases the new tires' thread design was such that there were wide grooves with solid strips next to them (as shown in my post above). The Dunlop's do have the same kind of thread design, but there may be another issue involved as well because some of us with the staggered Dunlop's, AS, and sport package are not having tramlining problems.........YET.

Maybe another batch of defective Dunlops??

rodybmw

Hmmmm.........maybe we are talking about two different things. I will try to clarify what I am talking about.

The type of road imperfections that cause the problem that I am thinking of as "tramlining" are things such as:

1. The shallow "lines" or "grooves" that run in freeway lanes that I guess are supposed to provide better grip when the surface is wet.

2. The dividing lines between two different slabs of concrete. You can usually see these between concrete lanes in freeways. However, sometimes they "redraw" the lines separating the lanes and end up putting these dividing lines within the lane, exacltly where the tires on one side of the care end up at.

The type of road imperfection that I am NOT talking about is deep & wide holes, cracks, grooves, or dips that can cause imbalance in any car.

Ågent99

Rody,

Yeah, I think we are or at least *I* am!

Okay, I haven't noticed the tramlining (as defined by Rody) on my 545i/SMG with the Dunlop RFs and I recently put 4700 miles on her driving through British Columbia and Alberta (Canada).