Tire Talk Megathread

[rg1220]

My PSS aren't directional, though. They're marked outside/inside. I assume you wouldn't do that for those?

Also, for people who do a lot of tire changes (and do their own work), does anyone actually buy a tire machine and balancer? Something I'd be tempted to do in the future.

[DrFerry]

Originally Posted by rg1220

My PSS aren't directional, though. They're marked outside/inside. I assume you wouldn't do that for those? Also, for people who do a lot of tire changes (and do their own work), does anyone actually buy a tire machine and balancer? Something I'd be tempted to do in the future.

Correct. Your PSS are not directional, but they are asymmetric and employ dual tread compounds as one design strategy i.e. the outer tread shoulder compound is dry focused and different to the inner tread shoulder compound which is more wet focused.

The practice of flipping the tires on the rim has merit only in a dry track environment and only when a homogenous tread compound is employed with a non directional tread design. The Michelin PS2, PSS and PS4S tire product lines all use asymmetric, dual compound, design strategies. Hence, there is a reason why their inner sidewall states "Inside".

To paraphrase what others have already stated in earlier posts: With some tires, used solely on a dry track, flipping them on the rim has been done to extend tire life in a track application. However, one has to be very careful of the engineering constraints designed into the product to avoid not degrading dry grip, vehicle balance, and stability [assuming a dry track].

For example: Below is a photo of an OEM PSCup 2 tire that uses 3 different compounds across the face of its tread. So flipping this type of tire can reduce dry grip when the alternative wet compound focused tread shoulder faces the outside.
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Here's an illustration of the PS4S dual compound design strategy.
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And PSS
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Source link and other more detailed information:
https://motoiq.com/not-all-michelin-...ed-the-same/4/
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Not to confuse things any further, but if a directional tire were to be flipped on the rim and used in a wet environment its tread will actually pump water "into" the contact patch rather than away from it.. This is the reason why directional tires use a marking of some type to indicate the direction of rotation in service.

[derbo]

Originally Posted by DrFerry

Correct. Your PSS are not directional, but they are asymmetric and employ dual tread compounds as one design strategy i.e. the outer tread shoulder compound is dry focused and different to the inner tread shoulder compound which is more wet focused.

The practice of flipping the tires on the rim has merit only in a dry track environment and only when a homogenous tread compound is employed with a non directional tread design. The Michelin PS2, PSS and PS4S tire product lines all use asymmetric, dual compound, design strategies. Hence, there is a reason why their inner sidewall states "Inside".

To paraphrase what others have already stated in earlier posts: With some tires, used solely on a dry track, flipping them on the rim has been done to extend tire life in a track application. However, one has to be very careful of the engineering constraints designed into the product to avoid not degrading dry grip, vehicle balance, and stability [assuming a dry track].

For example: Below is a photo of an OEM PSCup 2 tire that uses 4 different compounds across the face of its tread. So flipping this type of tire can reduce dry grip when the alternative wet compound focused tread shoulder faces the outside.
.

.
Here's an illustration of the PS4S dual compound design strategy.
.

And PSS
.

.
Source link and other more detailed information:
https://motoiq.com/not-all-michelin-...ed-the-same/4/
.
Not to confuse things any further, but if a directional tire were to be flipped on the rim and used in a wet environment its tread will actually pump water "into" the contact patch rather than away from it.. This is the reason why directional tires use a marking of some type to indicate the direction of rotation in service.

Great to note assymetric compounds since the star spec PS4S for BMW G80 now have 5 alternating compounds!

[DrFerry]

Originally Posted by derbo

Great to note asymmetric compounds since the star spec PS4S for BMW G80 now have 5 alternating compounds!

"Let the Engineers run wild but get the business!".. Technically only 3 compounds but laid in 5 different positions across the tread face. Black, Red and Green strips. Not to mention the option of different compounds under the tread or even within it.. The Black Art of compounding rheology.
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[derbo]

Originally Posted by DrFerry

"Let the Engineers run wild but get the business!".. Technically only 3 compounds but laid in 5 different positions across the tread face. Black, Red and Green strips. Not to mention the option of different compounds under the tread or even within it.. The Black Art of compounding rheology.
.

yeah, I should've been more clear, it was just 5 alternating compounds with 3 different materials lol. Even then, it is interesting the compund of black carbon is different from the aftermarket PS4S too. Carbon+ vs Carbon+++

Still interesting regardless!

[DrFerry]

Recently updated Grassroots Motorsports article on May-29-2022:
Ultimate track tire guide | 200tw, 100tw, street-legal track and R-comps
https://grassrootsmotorsports.com/ar...-buyers-guide/
.

[Kelse92]

In the comments it says nothing was actually updated and their editor made a mistake, oops lol
They should have tests on the Goodyear RS, Bridgestone RE71rs, and the Nexen NFera Sport soon though I would think

[Richneerd]

Now I think I know why I might be at the limit with my Super Sports

[omgzirra_exe]

V730 stats are top tier :P

[Davisca455]

Originally Posted by omgzirra_exe

V730 stats are top tier :P

I noticed that as well when I was trying to figure out my track tire/wheel setup.
The issue for me was sizing.
275/35/18
305/35/18

The NT01 checked the most important boxes for me.

In order of importance:
1) Heat Tolerance (don't like it when my tires get greasy)
2) Wear (I feel bad when Suzanne asks me "Didn't you just buy tires?")
3) Sizes
4) Pace (was only a B, but I don't need to set the world on fire to have fun at an HPDE)
5) Wet (Have the PS4s if it rains)

[slcook54]

Still planning on ECF next. Seems to have all the great traits of the rs4, but a little faster. Should be a nice upgrade from PS4s.

[b4hand]

I'll probably do NT01 too

[PrimeBMW]

Originally Posted by b4hand

I'll probably do NT01 too

Do the NT01 still make that awful noise that drowns out the beautiful sound the S65 makes? Or wait. Was that the R888? I lump those together.

[DrFerry]

Originally Posted by PrimeBMW

Do the NT01 still make that awful noise that drowns out the beautiful sound the S65 makes? Or wait. Was that the R888? I lump those together.

By the looks of the NT01 tread design I'd say it's been specially designed to emulate the sound of bad wheel bearings at speeds over 45mph (or perhaps even lower).
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Nitto NT01

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https://www.nittotire.com/competitio.../#pdp-features

[rhyary]

New MPSS courtesy of NYST and sub 1:39 pace
Need to test the "Force" on this track!

[DrFerry]

[Gossypiboma]

Originally Posted by PrimeBMW

Do the NT01 still make that awful noise that drowns out the beautiful sound the S65 makes? Or wait. Was that the R888? I lump those together.

I dont drive the NT01s on the street but I don't hear much noise on the track.

Its a fast rack tire who cares what it sounds like. They shouldn't be street driven anyways.

[911r]

Originally Posted by PrimeBMW

Do the NT01 still make that awful noise that drowns out the beautiful sound the S65 makes? Or wait. Was that the R888? I lump those together.

R888R is the worst road noise I have ever experienced from a tire. NT01 wasn't bad…or as bad.

[PrimeBMW]

Originally Posted by Gossypiboma

I dont drive the NT01s on the street but I don't hear much noise on the track.

Its a fast rack tire who cares what it sounds like. They shouldn't be street driven anyways.

I care 😃. Part of the joy of driving the e92 M3 is the sound of that engine. I just don't see the point of that tire. There are other options that are much better unless you don't mind being passed.
Seriously. I get unreasonably angry about that tire 🤣

[Gossypiboma]

Originally Posted by PrimeBMW

I care 😃. Part of the joy of driving the e92 M3 is the sound of that engine. I just don't see the point of that tire. There are other options that are much better unless you don't mind being passed.
Seriously. I get unreasonably angry about that tire 🤣

Honestly the NT01 isnt that loud on track. You really can't hear them over the engine sound.

What tires are you referring to that are faster? I am very fast with the NT01s and a factory suspension car. I rarely am passed. If you look at the grassroots motorsports chart posted in this thread there aren't many other options. I'm actually interested in your answer, not just being a jerk.

If I want a 18" track day tire, dont care about wet performance or noise whats the best tire?

[DrFerry]

Originally Posted by Gossypiboma

Honestly the NT01 isnt that loud on track. You really can't hear them over the engine sound. What tires are you referring to that are faster? If you look at the grassroots motorsports chart posted in this thread there aren't many other options. I'm actually interested in your answer, not just being a jerk. If I want a 18" track day tire, dont care about wet performance or noise whats the best tire?

How about the V730, Proxes RR or A052?
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[Gossypiboma]

Originally Posted by DrFerry

How about the V730, Proxes RR or A052?
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I was planning on trying the Proxes RR actually. Supposedly they are the same compound as the NT01. The A052 has a horrible heat tolerance rating so its gonna fall off fast after a few laps.

I'm interested in the V730, but finding a direct comparison is difficult. I've also read they are quite narrow.