Are my "track" tires too worn out for another track day?

[PCV]

Hi all. Need your opinions about this. Since latter half of last summer, I've been using Michelin PS2's as my dedicated track tires on my C55. So far, they've gone through 3 track days (twice at Mosport, and once at Shannonville). On the track, I increase the air pressures about 3-4 psi above the recommended. After some hot laps, my tire pressures are in the low 40's psi.

I've been rotating the tires from side to side between each of the track days. The tread in the middle and inside edges are fine. Not surprisingly, the outside edge is wearing out the most, especially in the front. My suspension is stock AMG.

Are my tires still safe to use on the track despite the wearing out of the outside edges? (I certainly hope so.) Here are 2 pics to show my worse tire. I find Shannonville to be much more abrasive for my tires than Mosport.

http://img80.imageshack.us/img80/7606/photo2537smallds2.jpg

http://img80.imageshack.us/img80/5337/photo2538smallqq1.jpg

[Yorgi]

Those look like they are still good for one more track day.

You have a lot of tread on the middle of the tire so I would have a tire shop "flip them over" to the rims on the opposite side of the car so the worn outer shoulders are on the inside. If you do that I think you will get another 3 days out of them. You might want to go up another 2 PSI or more to reduce the shoulder wear. You are getting pretty bad shoulder roll as you can see wear way up the sidewall almost touching the "Michelin" logo.

When you start getting near the end of the tires life, check for cording (white strings showing) after each session. If you see strings then it's time to stop. :sick:

[webbie]

why are you asking? aren't you going to bring the new car to fastlap? :rolleyes:

Like Rick said, flip them for ~$80 and may get you 2 shannonville or 3 mosport days. I found benz eat up the front tires faster than bimmer.

[PCV]

I'm not quite sure I understand about "flipping the tires". The PS2's are non-directional, but the tread/compound is different on the outside and inside portions of the tread. In other words, there is an "outside" and "inside" side to the tires.

If I understand you guys correctly, you want me flip the tire such that the "inside" part is on the outside, and vice versa. Is that safe?....especially when the tire is designed to be installed the other way around?

[webbie]

arrggh, should had use RA1, you can mount it anyway you like.

You've got a good point, according to the book, you cannot flip them because of the compounds.

Put another track day on it, watch out for cording after each session, and then they will be street use only.

[carboy88]

I'm not quite sure I understand about "flipping the tires". The PS2's are non-directional, but the tread/compound is different on the outside and inside portions of the tread. In other words, there is an "outside" and "inside" side to the tires.

If I understand you guys correctly, you want me flip the tire such that the "inside" part is on the outside, and vice versa. Is that safe?....especially when the tire is designed to be installed the other way around?

Yeah you should not flip tires with asymmetrical tread patterns.

[Yorgi]

You can run asymmetrical (directional) tires backwards in the dry. The only thing affected when you run an asymmetrical tire backwards is the wet performance; water will not evacuate properly. They might also get noisy.

I'm not sure about the PS2's dual compound composition though. It might make a bit of a difference if you run it backwards. I would not do that on the street but for dry track-only use I would try it. Maybe search some forums for someone who has tried it.

[glenspeed]

the tires look totally fine. you even still have grooves showing, meaning there is lots of tread depth left. like Yorgi said, until you see white threads/cords showing, there's alot more life in those tires.

yah, in the dry you can run tires any way, asymetrical or not.

run them until you cord or chunk them.