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Thanks for the reply. A rule of thumb I usually go by with the UTQG wear rating is multiply the number by 200 to get the life of the tire in km. But where I live we get so much rain the life becomes significantly longer. The original set of Goodyears I used year-round on my old Ford Windstar lasted over 100,000km and still had quite a bit of tread left when I replaced it with Bridgestone Turanzas. Those Goodyears had a UTQG rating of 350.
 

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Interesting thoughts. So do you (and anyone else) actually recommend "downsizing" to 205/50 or 55 on stock or equivalent wheels?[/b]
Yes to the 205/55, if the chosen tire is the Yokohama ADVAN Sport. No to a 205/50 of any brand.
 

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I think what he's saying is Advans at 205/55 *could* outhandle Toyo T1-R at 225/45. And I seriously doubt that is consistently repeatable with the larger (more flex-susceptible) sidewall

Of course, if he means 205/55 will always outhandle 225/45 of any given kind of tire, he's high :)

Oh, btw - even IF he were right on the first one - I *only* want 225/45 or even 215/45 or 215/50 - not 205/55.
As far as rotational diameter goes, all these sizes are close enough to be just fine - in fact, even on my 16s, I run 215/55 :)[/b]
O.K.: Let us assume that a 205/55 tire has a section width of exactly 205mm and an aspect ratio of exactly 55 percent. (Actually, it has a section width anywhere between 200mm and 210mm and an aspect ratio anywhere between 52.5 percent and 57.5 percent. See the sidebar below.) Let us also assume that a 225/45 tire has a section width of exactly 225mm and an aspect ratio of exactly 45 percent. Then the length of the sidewall of a 205/55 tire is 205 x 0.55 = 112.75mm, and the length of the sidewall of a 225/45 tire is 225 x 0.45 = 101.25mm. In that case, the difference in length between the sidewalls is 11.5mm, or 9/20th inch, not that much a difference in the greater scheme of things. However, on a 7" rim, the sidewall of the 225/45 tire will be cinched in like this: \ /, whereas the sidewall of the 205/55 will be closer to straight up-and-down, like this: ||. The 205 is more likely to handle in a symmetrical manner in response to lateral forces than the 225/45 will (on the 7" rims) for that reason alone. The concept is explained, in somewhat different terms, at this link.

As to flex susceptibility, many other factors than length enter in. Most high performance tires -- including the Yokohama ADVAN Sport -- have inserts in the sidewalls to fine-tune the flex. A "touring" tire with an identical sidewall length to an ultra-high performance tire will, mounted on the same rims, have more flex, in order to give a softer ride. The technology is in place to give a tire whatever flex is appropriate, more or less without regard to the sidewall length (within reasonable parameters, of course). As you undoubtedly know from your experience with the Toyo T1-S, they give an outstanding ride and good road roughness absorption, at the (acceptable to many) cost of a little vagueness in steering precision -- at least that was my experience with those tires in the 225/55R16 size. However, that size is one of the sizes in which Toyo employed polyester as the body (carcass) plies. Perhaps the sizes in which Toyo used rayon for the carcass material handled more precisely.

The fact is, among tires that fit on a 7" rim, a 45 aspect ratio is too short for any tire that has an adequate load index for a Mazda6. If you want a 225 section width on a 7" rim, you should go wth a 225/50. Or, if you want a 225/45, you really should be looking at a 7.5" rim. (The 215/45, if you could find one, would bee too small, and effectively would alter your gear ratios.)

The contact patch of a 205/55R17 tire inflated to 35 psi will be the same size as the contact patch of a 225/45R17 tire inflated to 35 psi -- the same amount of "rubber on the road" -- but the shapes of the respective contact patches will be different. The 45-series tire will be more susceptible to outside inputs (from the steering wheel or from irregularities in the pavement) to effect a change in direction, compared to the 55-series tire. Conversely, compared to a 225/45, a 205/55 will have more of a gyroscopic action ("wanting" to stay pointed in the direction they are rotating) than the 225/45 will, and will tend to track better. That will make the steering of the 205/55 a bit less "twitchy," thus requiring fewer micro steering corrections, than the 225/45 when traveling down a straight road, all other factors being equal.

SIDEBAR: as to the precision of a specific size designation, let us compare two 205/55R17 ultra high performance tires, the Michelin Pilot Sport PS2 and the Continental ContiSportContact 2. According to the respective manufacturers' data sheets, the 205/55R17 Continental will get 844 revolutions per mile, and the 205/55R17 Michelin will get 803 revolutions per mile, which indicates a 5.1 percent difference in overall diameter of the respective mounted tires. Plug that into your on-line tire size calculators.
 

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(The 215/45, if you could find one, would bee too small, and effectively would alter your gear ratios.)[/b]
Not that I disagree - after my brief experience with 215/50 on 17x7, I think this size is more appropriate - but if what you're saying is true, then why did the 6 sold in our part of the world have 215/45R17 as the "stock" size?
 

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after my brief experience with 215/50 on 17x7, I think this size is more appropriate - but . . . then why did the 6 sold in our part of the world have 215/45R17 as the "stock" size?[/b]
Beats me :headscrat:
 

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Not that I disagree - after my brief experience with 215/50 on 17x7, I think this size is more appropriate - but if what you're saying is true, then why did the 6 sold in our part of the world have 215/45R17 as the "stock" size?[/b]
The American car-buying public likes cushier rides -hence the greater sidewall.

I believe the two available optional wheel/tire sizes in Europe (in 15 and 16) match the 215/45-17 ratio better. And that the car's gearing is designed to use those.

I don't doubt they've recalibrated the speedos installed on North American 6's for 215/50-17 and 205/60-16, though!
 

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225/50/R17 Bridgestone Potenza RE960 AS Pole Position tires (4) installed last night.

Pics and thoughts to follow....
 

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I just had 4 GoodYear Eagle ResponsEdge 215/50/17 put on the stock 17" rims on my 2003 6s, replacing the OEM tires.

Was looking at the Falken 512s, Toyo, and one place had suggested the Yokohama AS430 also. After looking at reviews, and talking to a few local tire dealers, I decided on the Goodyears. I was looking for a tire to replace the old OEMs which are getting bad, and for something that hopefully handles better in snow/slush then the OEMs. With the OEMs, I could barely get in my drive way the first winter after I got the car when there was just a inch of snow on it.
 

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225/50/R17 Bridgestone Potenza RE960 AS Pole Position tires (4) installed last night.

Pics and thoughts to follow....[/b]
I went with the 215/50/17 Bridgestone Potenza RE960 Pole Position tires.

Had them installed last Wed.

So far, so good - excellent tires.
 

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Dunlop Direzza DZ101 215/50/17 on stock 17" rims. Very pleased.[/b]
Stop lyin'. These tires are garbage... :laugh: :laugh: :laugh:

I'll say good-bye to the DZs in a week when I get some Kumho Ecsta SPTs...
 

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Stop lyin'. These tires are garbage... :laugh: :laugh: :laugh:

I'll say good-bye to the DZs in a week when I get some Kumho Ecsta SPTs...[/b]
They really do stuck... I was mad at Hubby for getting them...
 

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Stop lyin'. These tires are garbage... :laugh: :laugh: :laugh:

I'll say good-bye to the DZs in a week when I get some Kumho Ecsta SPTs...[/b]
They really do stuck... I was mad at Hubby for getting them...[/b]

Jeez, what's with you guys. You hear me putting anything down about whatever you've got goin? When this thread was started, I didn't realize it was a setup to be shut down. All I did was answer the question, "What Tire Brand You Have?" Thanks for the ambush - later .
 

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Jeez, what's with you guys. You hear me putting anything down about whatever you've got goin? When this thread was started, I didn't realize it was a setup to be shut down. All I did was answer the question, "What Tire Brand You Have?" Thanks for the ambush - later .[/b]
Didn't mean to make you feel ambushed... It's just that they really do suck, they are always slipping... But I guess they must be working for you since you are very pleased...
 

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Didn't mean to make you feel ambushed... It's just that they really do suck, they are always slipping... But I guess they must be working for you since you are very pleased...[/b]

There was no "feel" about it, I was ambushed.

My experience so far is that they stick one hell of alot better than the OEM tires. There's alot to take into concideration with tire response and it's not just only the tires. The entire suspension and drivers abilities come into play as well. I've tested these tires out in extreme cornering on mountain roads and so forth, and for my needs they're a great improvement over the OEM tires. What was interesting is I did a search on the forum and couldn't find anything by any members about these tires, but that's not the boards fault. For all I know, Dunlop may have made some changes since you guys last had yours installed. Anyway, I'm not lying to anyone and really am impressed with the ride, handling, and quietness of the tires. With that said, I'm movin' on to another thread. Have a good one.
 
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