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[gan1hck]

I run my car at a track that has more right hand turns than left hand turns....enough so that after a few track days, you can see that the left side of all four tires (AD08R's) are worn more.

My question is 2 fold.

Is it safe to run the AD08's backwards on a completely dry track?

and if safe, will running backwards damage the tire carcass or shorten it's life span?

Or is this just a plain stupid question???

any and all opinions/experience are welcome!!!

[Flea7]

Originally Posted by gan1hck

I run my car at a track that has more right hand turns than left hand turns....enough so that after a few track days, you can see that the left side of all four tires (AD08R's) are worn more.

My question is 2 fold.

Is it safe to run the AD08's backwards on a completely dry track?

and if safe, will running backwards damage the tire carcass or shorten it's life span?

Or is this just a plain stupid question???

any and all opinions/experience are welcome!!!

Some teams did this last year in formula one and the tire delaminated. It tore it self apart due to the way it was made. It was unraveling it self by sending it in the opposite direction it was meant to go.

I'm no expert in how tires are made....especially ones compared to F1Perelli's ....but I just wanted to put it out there.

[gan1hck]

Originally Posted by Flea7

Some teams did this last year in formula one and the tire delaminated. It tore it self apart due to the way it was made. It was unraveling it self by sending it in the opposite direction it was meant to go.

I'm no expert in how tires are made....especially ones compared to F1Perelli's ....but I just wanted to put it out there.

I think they were flipping tires like the PSS's where there is a defined outside/inside side to the tires even though they were not unidirectional tires.

Anyways...would love to hear personal experiences/practices.

[Flea7]

Originally Posted by gan1hck

I think they were flipping tires like the PSS's where there is a defined outside/inside side to the tires even though they were not unidirectional tires.

Anyways...would love to hear personal experiences/practices.

To my understanding, the Pirelli's were made unidirectional and that running them on the other side made them come apart. Team did this to save tires during practice and qualifying. When this practice was done with Michelins they did not come apart.....I guess it was a different story when F1 switched to Pirelli's.
Steve Matchett was explaining it during one of the pre-race about the aftermath of many of the tires delaminating during high speeds.

Anyhow, I'm not sure how consumer unidirectional tires are made so this may be irrelevant. I too would like to hear personal experiences.

[gimmethemuumuu]

I don't track but I've switched tire directions on my cars for a few years now. It promotes more even wear (by allowing side-to-side rotation) and naturally reverses feathering created through normal tire usage. I've not experienced any abnormal tire degradation or handling issues with this approach.

[Amirsm3]

Originally Posted by gimmethemuumuu

I don't track but I've switched tire directions on my cars for a few years now. It promotes more even wear (by allowing side-to-side rotation) and naturally reverses feathering created through normal tire usage. I've not experienced any abnormal tire degradation or handling issues with this approach.

What tires are you doing this with?

[gimmethemuumuu]

Originally Posted by Amirsm3

What tires are you doing this with?

I can't remember which ones are truly directional. But I have done this with both my winter Continental ExtremeContact DWS's and my summer Michelin PSS's.

I've also done the same with my wife's car for years. It's running General Exclaim UHP's.

[jhbrennan]

Directional tires have a direction of rotation arrow on the sidewall.

Asymmetrical tires have something like "this side out" on the sidewall. The PSS are asymmetrical.

[Amirsm3]

Originally Posted by gimmethemuumuu

I can't remember which ones are truly directional. But I have done this with both my winter Continental ExtremeContact DWS's and my summer Michelin PSS's.

I've also done the same with my wife's car for years. It's running General Exclaim UHP's.

Oh okay. Just curious is all. I know not every tire is manufactured equally, so I wanted to gauge what brand/model you were doing this with.

[kwality]

OP, i think the option is to dismount and mount the directional tires to properly rotate. this will cost a bit of money each time.

or run these to the ground and then get asymmetrical all around - staggered or non-staggered.

this way they can be rotated side to side and to the fronts if non-staggered.

[gan1hck]

Originally Posted by kwality

OP, i think the option is to dismount and mount the directional tires to properly rotate. this will cost a bit of money each time.

or run these to the ground and then get asymmetrical all around - staggered or non-staggered.

this way they can be rotated side to side and to the fronts if non-staggered.

Can't remount....all four tires are wearing more on the left side due to a mostly right turning track.

Should have kept with asymmetricals like the PSS's that allowed side to side rotation...but the AD08's last longer in the heat.

[ben@tirerack]

In general, a directional tire run backward will work fine in the dry.

An asymmetric tire should not be run inside out, because the shoulder designed for the inside is not as effective in dealing with heavy cornering loads.

[dogbone]

I've run Hankook RS-3 and Hankook TD backwards many many times and they run great either way. In fact, I've set some of my personal bests with the tires going backward. (Always in the dry.)

[4corners]

I checked mine. My front conti's are 'this side out' and my rear Hankook's are directional. I swapped the front one's today to even them out a little. My right one wears a little faster on the inside edge. Both tires had cracks on the inside of the tire, as if it were delaminating. but just in a few places. Probably from potholes and back bridge decks impact.

[happos2]

Originally Posted by gimmethemuumuu

I can't remember which ones are truly directional. But I have done this with both my winter Continental ExtremeContact DWS's and my summer Michelin PSS's.

I've also done the same with my wife's car for years. It's running General Exclaim UHP's.

Need any new DWS's? I have 245/275s (19s) sitting in the basement!

OP, Answered this in the track section. Directional (only directional, not asymmetrical) are fine running backwards.

[gimmethemuumuu]

Just to be clear, I'm not remounting the tires on the wheels--just switching the wheels from side to side. So, the same side of the tire is always to the inside. So, if I'm understanding correctly, this approach shouldn't be a problem, even with assymetrical tires.

[gimmethemuumuu]

Originally Posted by happos2

Need any new DWS's? I have 245/275s (19s) sitting in the basement!

Nah. Thanks though. The tires have been decent. However, as soon as I get through these, I think I'll run winter tires in the winter instead of all-seasons.

[jhbrennan]

Originally Posted by gimmethemuumuu

Just to be clear, I'm not remounting the tires on the wheels--just switching the wheels from side to side. So, the same side of the tire is always to the inside. So, if I'm understanding correctly, this approach shouldn't be a problem, even with assymetrical tires.

Asymmetrical can be switched side to side - outside will always be outside. If you switch directional side to side they direction of rotation will be reversed.

[happos2]

Originally Posted by gimmethemuumuu

Nah. Thanks though. The tires have been decent. However, as soon as I get through these, I think I'll run winter tires in the winter instead of all-seasons.

Understandable. Ran the DWS 2 winters ago and switched it up to Blizzaks this past winter. Big difference.

[ben@tirerack]

Originally Posted by gimmethemuumuu

Just to be clear, I'm not remounting the tires on the wheels--just switching the wheels from side to side. So, the same side of the tire is always to the inside. So, if I'm understanding correctly, this approach shouldn't be a problem, even with assymetrical tires.

Correct.

[dparm]

There is always a lot of confusion around asymmetrical versus directional.

Asymmetrical means there is a definite inside and outside. The sidewall will be labeled as such (aka "OUTSIDE"). As Ben said, the compound and construction can vary so running them incorrectly could cause premature failure. Asymmetrical tires usually have large blocks on the outside to maximize dry traction, and small blocks on the inside to maximize wet traction.

Directional means they must rotate in a particular direction. The sidewall will be labeled as such (aka "ROTATION" --->). Running them backwards could cause the tread pattern to be less effective at evacuating water, for example. I don't know if it would cause the tire to come apart, but it seems plausible. Anecdotally I have heard that directional tires tend to perform well in wet weather because they don't have to make compromises in the tread design.

This site explains it well:
http://www.barrystiretech.com/direct...icaltires.html

[smmmurf]

Originally Posted by dparm

There is always a lot of confusion around asymmetrical versus directional.

Asymmetrical means there is a definite inside and outside. The sidewall will be labeled as such (aka "OUTSIDE"). As Ben said, the compound and construction can vary so running them incorrectly could cause premature failure. Asymmetrical tires usually have large blocks on the outside to maximize dry traction, and small blocks on the inside to maximize wet traction.

Directional means they must rotate in a particular direction. The sidewall will be labeled as such (aka "ROTATION" --->). Running them backwards could cause the tread pattern to be less effective at evacuating water, for example. I don't know if it would cause the tire to come apart, but it seems plausible. Anecdotally I have heard that directional tires tend to perform well in wet weather because they don't have to make compromises in the tread design.

This site explains it well:
http://www.barrystiretech.com/direct...icaltires.html

All of the best rain tires are directional: Hoosier/Michelin rain race tires are incredibly good in deep puddles. Toyo R888 are decent. Yokohama AD08R are surprisingly good in the wet w/ standing water for being dry focused street tires.

That said, there are some non directional, asymmetric street tires that are excellent in the rain (Bridgestone S04, Conti DW, Michelin PSS).

The directional rain tires are very delicate. They have soft compound optimized for cold temperatures and the biting edges of the tread blocks wear off quickly depending on how wet conditions are, how hard they are being driven, and how coarse the surface is. They pack a lot of tread density yet offer significant water evacuation while they are new, but they quickly lose their edge (literally).

Obviously most street drivers don't have $1400 for a set of directional rain tires every couple hundred miles. Hence, I think the more common design for street tires (asymmetric) was chosen because it is more robust for wear with tread grooves spanning the circumference of the tire yet still effective in the wet. Asymmetric designs also allow manufacturers to optimize the outside shoulder for dry performance (think PSS). The outside tread doesn't have to be so great in the rain since lateral loads are not as high in the wet and the middle/inside of the tire is worked harder (assuming some neg. camber in the alignment).