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[AltecBX]

Dunlop Direzza Sport Z1 Star Spec against the Bridgestone Potenza RE-01R?

Which one?

[AltecBX]

Can anyone tell me what this says in Japanese?

http://4g63vim.wordpress.com/2008/02...eplace-re-01r/

[FourPtDrift]

Originally Posted by AltecBX

Dunlop Direzza Sport Z1 Star Spec against the Bridgestone Potenza RE-01R?

Which one?

You're comparing Apples to Oranges. The RE-01R is a class leader in what is virtually a class in and unto itself. Sidewall strength, tread surface, compound technology - you name it, the RE-01R is the leader. If you're looking for the highest specific performance tire that you can still drive safely on the street with... you'll not find anything better than the Bridgestone solution. Take a look on this forum, you'll find many threads that say the same.

-Daniel

[AltecBX]

Originally Posted by FourPtDrift

You're comparing Apples to Oranges. The RE-01R is a class leader in what is virtually a class in and unto itself. Sidewall strength, tread surface, compound technology - you name it, the RE-01R is the leader. If you're looking for the highest specific performance tire that you can still drive safely on the street with... you'll not find anything better than the Bridgestone solution. Take a look on this forum, you'll find many threads that say the same.

-Daniel

Even tirerack told me that the Dunlop Direzza Sport Z1 Star Spec are better than the RE-01R.

[FourPtDrift]

Originally Posted by AltecBX

Even tirerack told me that the Dunlop Direzza Sport Z1 Star Spec are better than the RE-01R.

Oh really? Was this Dave Tirerack or his brother Robert Tirerack?

Excuse the goofiness... but your statement is just as absurd. WHO told you this? Does the person have a name? Did Tirerack release an official announcement saying this and that's why you're using the global "tirerack" as an attribution for the claim?

No. I'm sorry. Just because you may speak to one rep, doesn't cut it. Do some reading and research.

First off, Tirerack did conduct a run-off review between the Direzza Sport Z1 (granted, not the Star Spec, but I'll get to that in a moment) along with the RE-01 and two other products, the Yokohama Advan AD07 and the BF Goodrich g-FORCE T/A KD.

Here are the results in short order:



Now, you're probably jumping to remind me that this test does not reflect the Star Spec. Good. Let's examine some basic metrics of the Star Spec product and what makes it different from its predecessor.

First, let's see what Tirerack DOES say about the Star Spec (editorial if you like, from Tirerack)

"The Direzza Sport Z1 Star Spec is for drivers who don’t want to wait as long for their tires to come in during initial runs, as well as drivers of lighter weight vehicles who are often confronted with the task of working tire temperatures up to the point of generating peak grip."

So, important note here. This is where reading between the lines becomes important. R spec and near R spec tires need to be brought up to a temperature before they come in their own. They don't work from a cold start. That's because serious track tires expect serious drivers to know how to manage their performance characteristics. So, the Star Spec is designed to "simplify" this process - especially for drivers of lighter vehicles. Hate to brake it to you kid, but this is NOT our car. The E9X is far from a light weight. That means the characteristics that caused the RE-01R to be dominant over the original Dirrezza are not addressed in the Star Spec. But, let's continue with Tirerack's editorial:

"The tire's internal structure includes two wide steel belts reinforced by JointLess Band (JLB) Technology spirally wound polyamide to provide strength, uniform ride quality and high-speed capability while steel cord reinforced, 2-ply polyester sidewalls help resist lateral deflection to provide responsive handling and cornering stability."

Now, how does this compare with the RE-01R?

"The tire's structure includes two wide steel belts reinforced by spirally wound nylon to provide strength and uniform ride quality and high-speed capability while the sidewalls are reinforced by steel cord that helps resist lateral deflection providing responsive handling and cornering stability."

Seems similar. Until you pay attention to the ingredients. Sorta like grocery shopping. I'll cut to the chase. The sidewall on the RE-01R is more than twice the deflection strength of the Direzza Star Spec. 200% greater. I know what I want on my +3,600 car. Not to mention there's the whole issue of tire sizes. Bridgestone has me covered. Dunlop? Not so much.

What's the RE-01R's ratings? Its a 140 Treadware AA Temp product. The Dunlop Direzza Star Spec? Oops. 200 Treadware. So... we have a stronger sidewall and STILL a stickier treadsurface with the Bridgestone product.

And then there's the all important overall rubber wearing engineering that goes into the tire... how the rubber responds to heavy track abuse. The RE-01R marbles up just like an R compound track tire. In fact, at track events, drivers of R compound tires would marvel at how my RE-01R's responded just like an R compound. This is a product of Bridgestone's advances in silica technology for tire compounding. If you think this is trivial.. you may want to take a look at the name of the tires used in Formula 1.

Look, I'm not going to say the Dunlop product is a bad product. Its not. Its a very good product. But for our cars, cold/inclimate weather not withstanding, the RE-01R remains the best solution, bar-none.

-Daniel

[AltecBX]

FourPtDrift, thanks for the writeup. I might have to think twice. When I called tirerack, twice this week, both representative told me the Dunlops are the best summer tires hands down. I told him what about the RE-01, and both told me they were great, but I asked them which was the best, and they said the Dunlops for extreme summer driving. They are cheaper, but the only down size is the wear on the tires.

[FourPtDrift]

Originally Posted by AltecBX

FourPtDrift, thanks for the writeup. I might have to think twice. When I called tirerack, twice this week, both representative told me the Dunlops are the best summer tires hands down.

And did they explain to you why? Did they explain how they had arrived at such a conclusion? Or was this just like saying "chocolate is better than vanilla ," and when pressed to explain "why" they'd answer "because."

Whenever a new product comes out in any retail environment... sales staff are always quick to jump and push it... simply because they have inventory... and its new. This is not a sale base on merits. Ask for explanations. Challenge the answers you're given and see what you get in reply.

I told him what about the RE-01, and both told me they were great, but I asked them which was the best, and they said the Dunlops for extreme summer driving.

Again.. I'd ask why. And they I'd ask the representatives what sort of track experience they have. Then I'd ask them what vehicles they've driven and over what period of time and at what tracks. I'd ask them what tires they had on those cars and what they thought of various handling characteristics.

Or you can just accept their explanation of "because."

-Daniel

[fedinand]

If you look at the track results here:
http://www.tirerack.com/tires/tests/...y.jsp?ttid=100

It looks like the dunlops outperformed the bridgestones - by a small margin dry and a much bigger margin in the wet. The bridgestones gave a better ride, but the test numbers all favor the dunlops and the yokos at the track.

[FourPtDrift]

Originally Posted by fedinand

If you look at the track results here:
http://www.tirerack.com/tires/tests/...y.jsp?ttid=100

It looks like the dunlops outperformed the bridgestones - by a small margin dry and a much bigger margin in the wet. The bridgestones gave a better ride, but the test numbers all favor the dunlops and the yokos at the track.

And I maintain as I did in the prior post that the results are only applicable of they match the controls of the customer - that is to say, the weight and power of the vehicle that is to be used with the tires is key for understanding the corner loading that the tires will contend with. The hard and fast empirical data of the tire itself (before it is even mounted on a car) clearly points to the RE-01R being considerably better equipped for the forces a 335 can generate compared to a normally aspirated '06 E90 325i. This can be established on paper, and in the real world - I've seen it... and I've done it.

-Daniel

[fedinand]

What your take on the Yokos? Cost aside, they seem to perform better than both the dunlops and bridgestones as a track tire.

[anerbe]

Originally Posted by AltecBX

FourPtDrift, thanks for the writeup. I might have to think twice. When I called tirerack, twice this week, both representative told me the Dunlops are the best summer tires hands down. I told him what about the RE-01, and both told me they were great, but I asked them which was the best, and they said the Dunlops for extreme summer driving. They are cheaper, but the only down size is the wear on the tires.

is this your daily driver car?

if you have a longer commute, the RE-01's may be a better bet (although wear may be an issue). If you have a short commute which may not allow enough time for warm-up, you may want to look at the dunlops.

what will your driving profile look like?

Mileage per day?
Road/weather conditions?
Expected wear?
Track events? Autocross/Road Tracks?

these tires excel at different things. your research should also include understanding what conditions you expect the tires to go through.

[AltecBX]

Is going to be my daily driving for the Summer and Fall. I have all seasons for the Winter and Spring. I drive hard in the rain. So I need a good wet tire as well, even though I have the xi.

50 Miles a day
NYC, 45 - 90 Degrees
Around 9,000 miles a year
Twice to track a year

[FourPtDrift]

Originally Posted by fedinand

What your take on the Yokos? Cost aside, they seem to perform better than both the dunlops and bridgestones as a track tire.

I've never known a "bad" pair of Yokohamas. They all tend to be very good to excellent product. BUT... and this is a big but... they don't load well... that is to say, they are not intended for heavy cars - which is why you don't see Yokohomas as OE on anything but the lightest of cars. The E9X isn't a 5 or 7 series... but it isn't exactly a lightfoot, either. The one big concern I would have with the Yokohamas is their ability to perform well with the weight of our car on them.

-Daniel

[lacartus]

Another data point...autocrossing

The Z1 SS appears to be the hot street touring tire for 2008, it's off to a win at the first tour event.

Recent ST history, as I recall:
Falken RT-615 was hot tire in 2006
replaced by Yoko AD7
replaced by RE-01R (still a great rain tire)
appears it will be replaced by Z1 SS

http://sccaforums.com/forums/thread/290995.aspx

[anerbe]

looking at your profile, it kind of splits both tires in regards to bias.

you can't go wrong with either tire, and with two track events/year, you won't notice the small % gap between the two.

would you be happy with a tire that lasts 10K mile, meaning you replace every year?

with the 50 miles/day, I would look into the tire that is lighter and has lower rolling resistance. however, for RR, i don't know the specs on these tires.

[FourPtDrift]

Originally Posted by lacartus

Another data point...autocrossing

The Z1 SS appears to be the hot street touring tire for 2008, it's off to a win at the first tour event.

Recent ST history, as I recall:
Falken RT-615 was hot tire in 2006
replaced by Yoko AD7
replaced by RE-01R (still a great rain tire)
appears it will be replaced by Z1 SS

http://sccaforums.com/forums/thread/290995.aspx

Very interesting link. Read through several posts. Some perceived the RE-01R to be softer... but there were concerns that the Z1 SS would chunk if not shaved before use. NOT what I want in a tire I'll take on the street. If I wanted to deal with that - I'd run a pure R compound and be done with.

I'll say it again... I think the Dunlop is probably a very good product... but not the right product for our cars... certainly not for my car as currently configured.

-Daniel

[AltecBX]

Originally Posted by FourPtDrift

Very interesting link. Read through several posts. Some perceived the RE-01R to be software... but there were concerns that the Z1 SS would chunk if not shaved before use. NOT what I want in a tire I'll take on the street. If I wanted to deal with that - I'd run a pure R compound and be done with.

I'll say it again... I think the Dunlop is probably a very good product... but not the right product for our cars... certainly not for my car as currently configured.

-Daniel

In that case, which one would you consider being you car is fully modded and a stock 335?

[FourPtDrift]

Originally Posted by AltecBX

In that case, which one would you consider being you car is fully modded and a stock 335?

Huh? Say that again please?

-Daniel

[AltecBX]

lol..What I meant to say, was which tire would you consider being your car is fully modded vs. a stock 335? Would you consider the RE-01 for both a modded and stock car?

Because you said "I'll say it again... I think the Dunlop is probably a very good product... but not the right product for our cars... certainly not for my car as currently configured.".

[FourPtDrift]

Originally Posted by AltecBX

lol..What I meant to say, was which tire would you consider being your car is fully modded vs. a stock 335? Would you consider the RE-01 for both a modded and stock car?

Because you said "I'll say it again... I think the Dunlop is probably a very good product... but not the right product for our cars... certainly not for my car as currently configured.".

Ok. I got ya.

Well, I suppose, the first thing I'd have to know is... if you're going to drive the car HARD... even in stock form, do you plan on shaving the tires before using them? With the caution that the Dunlops require shaving of tread depth to avoid chunking... to me... that's a big minus for a road tire... even one that is as "track oriented" as the Star Spec. Because of this issue, I'd still recommend the RE-01R.

-Daniel

[AltecBX]

I don't plan to shave the tires.

[Park2670]

With no experience with either of these tires, Id like to keep hearing reviews.