Best P185/60R15 for traction. LRR a plus.

[sbergman27]

I'm in the market for a set of P185/60R15 tires. The main priority is traction. Particularly on ice and snow and in rain. Secondarily, I'm also interested in low rolling resistance. I drive a lot of miles, and so thirdly, good tread wear would be a plus. I didn't realize that there was a traction rating higher than 'A'. There is: 'AA', met by only 3% of tires.

I have my eye on something like the Michelin Energy Saver A/S with the following specs:

ENERGY SAVER A/S Radial Traction:AA Temperature:B Tread wear: 480

Any suggestions?

-Steve

[severous01]

hahaha...185's and traction...good one

the best thing you can do for traction is go wider.

there's also not a lot of that tire size out there in different brands and they're all going to be an economy tire cuz they're for economy cars only. toyota is the only company i can think of that runs that size...well, maybe that old geo metro with aluminum wheels did...idk...either way, step it up a size and you'll get a lot more options

[sbergman27]

Originally Posted by severous01

hahaha...185's and traction...good one

My other car, with its P155/80R12 tires, seems to grip better on the ice an snow than the Yaris does. I'm not kidding. (Stock was P145/80R12, but those have been hard to find for a very long time.)

Keeping to a simplified physics model, frictional force is independent of surface area. But stopping on snow is not a simple system from a physics viewpoint. Lots of stuff going on.

Still, even going to something like a P205/55R15 only adds about 10% width, which is going to correspond to a < 10% difference in traction, since friction is, after all, and in general, independent of surface area. I suspect that tread design and material figures in pretty prominently compared to the limited range of width. Good snow clearing, taking advantage of opportunities for mechanical lock (as opposed to friction), and improved coefficient of friction change the *rules* of the game, rather than just adding a limited amount of (more of the same) width.

What *are* the limits, keeping the overall diameter within about 3% of stock, and without any scraping, for the Yaris anyway? Could it handle P225/50R15? That and P205/55R15 are the only close matches I can see with a 15 inch wheel.

P195/60R15 seems to be the widest *common* size. A 5% difference in width. 2% difference in overall diameter.

-Steve

Edit: Keep in mind, too, that the situation may be different for wet, M+S, and dry conditions. Then again, for years people have been letting air out if their tires in the snow, and swearing by it, despite the fact that Goodyear's testing has clearly demonstrated that practice to *reduce* traction on snow and ice.

[127.0.0.1]

Originally Posted by severous01

hahaha...185's and traction...good one

the best thing you can do for traction is go wider.

there's also not a lot of that tire size out there in different brands and they're all going to be an economy tire cuz they're for economy cars only. toyota is the only company i can think of that runs that size...well, maybe that old geo metro with aluminum wheels did...idk...either way, step it up a size and you'll get a lot more options

no.

traction rating on a tire is: how does it stop in wet ?
for any given tire size, AA is the best category for wet stopping.

wider tires wreck the AA rating. it may help cornering but doesn't
help wet stopping. unless it is a rain tire or happens to also be rated AA

wider tires ruin mileage
---
OP, stick with what you originally guessed. that is the tire

[sbergman27]

Originally Posted by 127.0.0.1

OP, stick with what you originally guessed. that is the tire

The width and/or the Michelin Energy Saver A/S?

As it turns out, P185/60R15 is, indeed, a weird size. The closest Energy Saver is P195/60R15. A 5% increase in tread width, and 2% increase in diameter. I do 95%+ of my driving on the Interstate highway. So the 2% increase in effective gearing is probably a help, if anything. And at 65 - 75 mph, air resistance dominates, accounting for something like 75% of total resistance at 75. As opposed to city driving, which is a mixed bag, but with air resistance figuring in decidedly less prominently.

Rotating mass is also less of a factor on the highway.

Still, I'd like to stay close to stock. And since I use the GPS and Scanguage as my speedometers, the 2% variance in diameter should be no tribble at all.

-Steve

[aca72]

I'll say this again...

Go with Michelin Harmony (185/60R15) and you're done.

DOT Quality Grades (UTQG Ratings)
Treadwear Grade 740
Traction Grade A
Temperature Grade B
http://www.michelinman.com/tires/pas...ony/35002/?tss

Check the reviews...
http://www.tirerack.com/tires/tires....omCompare1=yes

Pricey but worth it!

[dingbat]

Originally Posted by severous01

hahaha...185's and traction...good one

the best thing you can do for traction is go wider.

Depends entirely on the conditions. I used to auto-x a car of similar weight and design to the Yaris. I used 185's for the winter series races because anything wider would not come up to temp. on a car that size.

[RETRO]

Yoko Avid TRZ.

[SilverBack]

To be brutally honest, you're only gonna find econo tires in 185/60 size and nothing better. You need to move-up a size to sport tires for better results. I recommend Falken Ziex ZE-502 in 195/50 for your stock wheels (assuming it's for daily driving only). The treads are much more grippier on both wet and dry roads and at the same time the rubber is hard enough to last much longer.

I've been running those same Falkens but in 205/50 (wider than 195 because I also Auto-X) for the last 15K miles and I've never been more confident on the road. Right now the tread depth is unchanged minus the minor scuffing from Auto-X. Definitely worth it!

[yarrr]

First, traction and LRR are opposites.

Second, yes you get more traction with surface area, but less surface area allows you to "cut" through the snow/ice/standing water and hit pavement.

205s on the snow with a yaris isn't smart.

[sbergman27]

So far, the Michelin Energy Saver A/S in the P195/60R15 size looks like the best bet. They're all season, AA traction rating, and tested the best for RR, and well in other areas, out of the LRR tires Tire Rack tested here: Tire Rack LRR Tire Test.

At $113 a piece, they're a little pricier than what I usually buy. But the 480 treadwear rating (compared to 160 for the Bridgestone Potenzas that came on the car) makes up for that.

-Steve

[10DG22]

How many miles did the stock tires last you?

[ddongbap]

FYI, wider tires doesn't mean that the Yaris will grip more, or better.

[sbergman27]

Originally Posted by ddongbap

FYI, wider tires doesn't mean that the Yaris will grip more, or better.

Here is an excellent Walter Lewin Lecture from MIT Open Courseware. It addresses these issues.

[ddongbap]

Originally Posted by sbergman27

Here is an excellent Walter Lewin Lecture from MIT Open Courseware. It addresses these issues.

Aww, thats too much reading.

And I can't understand the advanced terms hes spitting out.

And he doesn't talk about weight ratings, and tire heat cycles. If you're unable to get the tires to its normal operating temps, they won't grip. Wider tires take longer to heat up. Also, wider tires don't necessarily have more contact patch.

btw, after reading the title, I'm pretty sure that the entire lecture doesn't cover real world issues and variables.

[Loren]

I skipped this topic originally, but since I like Steve, I'll dive in...

First, snow traction... narrower tires are favored over wider tires. You'll find that the recommended snow tire for any given car is almost always narrower than the standard tire. For REAL snow driving, the narrower tire cuts through the snow better to get to the pavement, where the wider tire will tend to ride on top of the snow. This is why your 155-shod Metro seems to get better snow traction.

For dry grip, wider is better... but excessively wide doesn't really gain you anything in street driving conditions. The 185 width is adequate for the Yaris, but as has been stated in this thread (I think... I just skimmed it), there are no real performance tires in that size.

Tires are a compromise. You're looking at all-season tires. Effectively, all-season tires are designed to do everything... but excel at NOTHING. Best bet if you have to drive in snowy conditions is to invest in a set of good snow/winter tires. Just like the best summer tires will amaze you with their dry grip (and some of them with their wet grip), a proper winter tire will astound you with its ability to cut through snow like it's not there, and find grip even on icy surfaces.

If you want one tire that does it all, you have to accept the compromises that come with it. Tires are getting better, though. As long as you're not looking for "extreme performance", there are some tires that offer a great set of compromises.

The AA traction rating that you mentioned is fairly new. The A rating had become almost irrelevant with modern tread compounds and tire designs, they needed something to address the better traction capability of modern tires. Like all tire ratings, it's pretty arbitrary, but a AA tire should be grippier than an A.

You're definitely on the right path looking at the Tire Rack. Great information there, thorough and unbiased testing, and great people.

Tire rack consumer ratings and reviews are good, too. But, always remember that the typical reviewer of any given tire is the typical BUYER of that type of tire. A low-budget all-season tire that's rated at 9 for traction can't be expected to have the same traction as an ultra-high-performance tire that is rated at 9... or even 8. The UHP tire buyer has higher expectations in that regard.

[Loren]

Also worthy of note... you could put just about ANY new tire on your car to replace the 3-year-old factory tires and the grip would be so much improved that you'd be impressed in most conditions. Tire rubber hardens as it ages. After 2 years, any tire will be noticeably less grippy. After 3 years... as far as I'm concerned, they're pretty hopeless and should be replaced regardless of mileage or remaining tread life.

[sbergman27]

Originally Posted by ddongbap

Aww, thats too much reading.

Don't read it! Watch it! :-)

Walter Lewin's lectures are works of art. Although this is, unfortunately, the one in this series where he's ill. Usually he ends up flying through the air between trapeze bars, electrified by a Vandergraff generator, or nearly decapitated by a Focault Pendulum, in order to underscore his trademark declaration: "Physics works!".

Each semester, he rehearses each lecture 3 times in front of an audience of at least one.

He does, BTW, address the temperature issue you bring up here. But slyly. He always leaves the students with at least one problem, with a non-obvious answer, to ponder. In this case, it's the width of race car tires.

I posted the link to OCW not so much to make an argument for wider or narrower, but because Walter is a very, very dedicated, cool, and inspirational professor, of a breed that this world could do with a lot more of. And, of course, it *is* pertinent to the topic at hand.

-Steve