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Discussion Starter #1
I recently purchased HRE 18x9 & 18x10 with Michelin PS2 in the stock size (245/40 & 275/35). The extra 1/2" of wheel width was added to the inside (increased backspace). Since mounting, the car has lost it's typical BMW on-center steering feel and now requires almost constant steering input. I first suspected the (new) wheel offset and its effect on the front end geometry, but a very experienced tire dealer and performance guru tells me that it's most likely the tires. Before I go through the gyrations of remounting the old (and very useable) factory tires, I'm curious if anyone else had had a similar experience with either Michelin PS2's or the offset issue.

Thanks for any input.
Jim
 

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Not sure that I can help you with your steering issue, but I do have a couple questions. First off, why did you choose to run a 245mm tire with a 9" wheel? You increased your front tire width 1" from the stock 8" to 9" HRE wheel. A more appropriate size would be 265/275mm for the fronts. Also, you said that the extra width was added to the inside, by increasing backspacing. I assume by that you mean you increased your offest?

Travis
 

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jvo said:
I'm curious if anyone else had had a similar experience with either Michelin PS2's or the offset issue.
I run PS2s in the summer on Dinan wheels (18x9 and 18x9.5). I run 265/35 on the fronts and 275/35s on the rear. I've not experienced the handling problems you're talking about. In fact, the first thing I noticed was how much better the car handled with wider fronts and how much more responsive the entire suspension was with the lighter Dinan wheels.

Although I am sure you checked, are you sure they mounted the asymmetic PS2 tires with the outside part of the tire facing out?

Jeff cherrsagai
 

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Discussion Starter #6
The answer to your "why" is that I entrusted the tire size issue to the dealer who was recommended to me; in retrospect, a poor decision, but at this time I'm simply trying to figure out which part(s) of this puzzle is (are) causing the problem. Your reply however, did cause a light to go off - I've had it in my head that the stock front width was 8.5", and therefore when I compared the backspace on the stock alloys to the HREs, it appeared that the extra 1/2" width was added in the form of offset. I'll have to take additional measurements to be certain, but this new revelation probably means that my offset is unchanged from stock, but that (as you correctly stated), the tire size is too narrow. This changes the puzzle pieces somewhat, but the question remains the same. Is the front wheel/tire size issue contributing to the "wander"?

Jim
 

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Jim,

The front wheel and tire combination is the only reasoning that I can come up with.

Good luck!

Travis
 

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Discussion Starter #8
x703jko said:
I run PS2s in the summer on Dinan wheels (18x9 and 18x9.5). I run 265/35 on the fronts and 275/35s on the rear. I've not experienced the handling problems you're talking about. In fact, the first thing I noticed was how much better the car handled with wider fronts and how much more responsive the entire suspension was with the lighter Dinan wheels.

Although I am sure you checked, are you sure they mounted the asymmetic PS2 tires with the outside part of the tire facing out?

Jeff cherrsagai
The tires are mounted correctly, but I'm somewhat reassured to hear that someone else is running 9's in the front and NOT having a "wander" issue with PS2's. Perhaps if I had 265/35s.......
 

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Hmmm...interesting situation...

I have BBS LM Wheels with Michelin PS2 Tires...The specs on the wheels and tires are 19" x 8.5" front and 19" x 10" rear with 245/35/19 front and 275/30/19 rear.

I have not had any "wandering" problems with my PS2 tires and the car drives like it should. Maybe you should try re-mounting some 255/35 or 265/35 on the front and make sure you get them high speed balanced and re-check alignment too. Sorry I couldn't help more...Hope this helps some though. :M5thumbs:
 
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