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[Maxsensation]

Picked up a spare mpss tire on the cheap and noticed tire thread differnce on both of them. Left one is practically new and the right one has about 5k miles. U can see the gaps are wider on the left tire than the one on the right. I wonder if this has to do with breaking it in and the heat cycle it goes through... Any ideas?

[ShocknAwe]

Production year on the side of the tire the same on both??

[gregthegr8]

Could also be if one has the BMW spec star on it and one doesn't? I know when I went from normal PSS to the bmw star ones, there was a very subtle difference in the pattern. So, look for the star logo on the side of one versus the other as well.

[Maxsensation]

Right one has a star and left one doesnt. When i loook at the side wall, the grapics, text and all are different. There both the same size, ratings, load and all.

One is a 2014 and the other is 2015. Not much difference in production time.

I wonder what difference in performace this causes.....

[gregthegr8]

Originally Posted by Maxsensation

Right one has a star and left one doesnt.

I wonder what difference in performace this causes.....

Ooh, I was right. I went through this when deciding on my rear tires, and after doing some research, reading this article, and hearing from an engineer who worked on the new NSX, he highly recommended getting the BMW star ones as they'll perform a lot better. They're like $10 more per tire, so worth it. However, I'm not sure what the ramifications are, if any, if you had a star spec one on one side and a non-star on the other. As you've seen, there are subtle differences, the compounds will be slightly different, so they may react differently. Whether that's something you can actually feel or tell? Don't know.

http://www.popularmechanics.com/cars...-same-9890716/

[Maxsensation]

Intresting... Ive went through many many sets of tires before and this is the first time i realize this. Good to know.

Given the contact patch, looks like one will be better in the dry and one will be better in the wet.

Theres like a 1cm gap difference in each tread

[tock172]

I was aware of the BMW Star Spec when I bought my upsized Michelin PSS, but I couldn't find them anywhere and ended up settling for the standard ones. Does anyone know where to source BMW Star Spec Michelin PSS in the 225/255 135i sizes?

[Maxsensation]

I bought mine from a 2series dude. Maybe the dealships has them??? There pretty costly to buy unused thou..

[juld0zer]

Originally Posted by gregthegr8

Could also be if one has the BMW spec star on it and one doesn't? I know when I went from normal PSS to the bmw star ones, there was a very subtle difference in the pattern. So, look for the star logo on the side of one versus the other as well.

Spot on.
The BMW star designated ones have narrower channels.
There's also some literature floating around that the front 225/40R18 tyres on the M135i were co-developed with Michelin to complement the car's handling.

The Bridgestone S001 is another tyre that has different channel widths for different intended vehicles (MB MOE vs BMW *), despite the same size on the sidewall.