StandardShift.com

Do you need winter tires if it doesn't snow?
"Despite the winter tires being dead in the middle of their operating range, and the summer tires much colder than they wanted to be, the winter tires took longer to stop the car than the summer rubber. That said, Fenske did say the car felt more stable with the winter tires despite taking longer to stop."

Read more: http://autoweek.com/article/products/do ... z53BQJIk6y

im gonna do a similar but more real-life test tomorrow. gonna see if my all-seasons can run in the snow. never changed over to the snows. may not have to. probably will...

Mine have been on since Octubre and have seen some muck. I still don't like them, but am curious of there's a rule of thumb for tire pressure. Should they be plumped higher or lower in terms of pressure than all-seasons? Thinking I could get better results by adjusting the pressure downward (currently at 39 psi as I remember reading somewhere there should be 4 psi more than summer; I could be misremembering though).

EDIT: After watching more closely I see that those are the tires that I've been using. I'd be curious to see him do a test with snow and ice on the ground, possibly with all-seasons as a control.

Not a big surprise. Instrumented braking tests would be dominated by grip with the surface (in cold temperatures, advantage anything but summer tires) but the subjective handling assessment well below the limit would be dominated by sidewall stiffness (advantage: summers).

Can we go back to calling them "snow tires" now?

They're designed for winter weather conditions in wintery places; they're made for snow and ice traction. I know everybody loves to talk about grip on dry pavement in cold temperatures, but ferchrissake any crappy worn-bald tire (no-season, summer, winter, whatever) will stick well enough on dry pavement. Sure, there are gains to be had with different compounds and better weather, but driving a shitty tire on -15F dry pavement isn't nearly as slippery as driving an excellent tire on snow.

Fenske tested, it sounds like, one specific set of summer tires against one specific set of winter tires. Winter tires and summer tires alike have softer compounds; it is all-season tires that have harder compounds. Besides questions of how they were designed/manufactured, the specific tires in question could have differences in age, storage, and especially wear.

Note that winter tires tend to come with deeper tread, large gaps, and heavy siping. If both sets were brand new, you could certainly expect the summer tires with shallower tread to do better on dry pavement, with all that deep flexible tread on the winter tires squirming.

I wouldn't bother with winter tires if I didn't deal with snow and ice.

tankinbeans wrote:Mine have been on since Octubre and have seen some muck. I still don't like them, but am curious of there's a rule of thumb for tire pressure. Should they be plumped higher or lower in terms of pressure than all-seasons? Thinking I could get better results by adjusting the pressure downward (currently at 39 psi as I remember reading somewhere there should be 4 psi more than summer; I could be misremembering though).

The label on your car remains the minimum, but if you're going to push it lower, probably better to do that in frigid weather when the pavement and air will help dissipate extra heat.

Letting air out won't net appreciably better grip strength? I'm speaking specifically winter since my winter tires have never been brilliant, thus my wondering if I'm using them wrong.

tankinbeans wrote:Letting air out won't net appreciably better grip strength? I'm speaking specifically winter since my winter tires have never been brilliant, thus my wondering if I'm using them wrong.

If you want better grip strength, then you've got to practice picken em up by the bead area and putin em down again, over and over again.until you can't hardly hang on any longer....Lather, Rinse and Repeat once a day and your grip strength will amaze you.

I still remember when Poplier Silence magazine went out to GM Milford Proven Ground and tested posi-traction (limited slip) vs open differential on a split-mu hill climb (Slippery on one side only). The car with posi didn't climb the hill as well as the car without....but it came down to car with posi had year-old snow tires and car without had new snow tires. From just sitting around for a year, the one set of tires wasn't as grippy as the other set. When they put new snow tires on the car with posi, it was clearly superior in this test.

Sew watt ewe wanna dew is buy new snow tars each and every year and sell them after their first winter.

theholycow wrote:Can we go back to calling them "snow tires" now?

They're designed for winter weather conditions in wintery places; they're made for snow and ice traction. I know everybody loves to talk about grip on dry pavement in cold temperatures, but ferchrissake any crappy worn-bald tire (no-season, summer, winter, whatever) will stick well enough on dry pavement. Sure, there are gains to be had with different compounds and better weather, but driving a shitty tire on -15F dry pavement isn't nearly as slippery as driving an excellent tire on snow.

amen brother cow. my all-seasons do pretty well without the snow and ice. a little slippage probably due to the tires hardening, but not bad at all.

Fenske tested, it sounds like, one specific set of summer tires against one specific set of winter tires. Winter tires and summer tires alike have softer compounds; it is all-season tires that have harder compounds. Besides questions of how they were designed/manufactured, the specific tires in question could have differences in age, storage, and especially wear.

yeah, for a scientist (engineer) who is clearly obsessed with the details, some of his testing at least seems suspect. different tires even of the same category can behave totally differently in different situations. i noticed this with my winterforce winter tires vs. the yokohama winter tires (forget the name). the winterforce tires also changed (mostly for the worst) as they got worn. i only used the yokos for one season, so didn't get to see how they aged. they seemed to be better as all-season tires than as winter tires though...

Note that winter tires tend to come with deeper tread, large gaps, and heavy siping. If both sets were brand new, you could certainly expect the summer tires with shallower tread to do better on dry pavement, with all that deep flexible tread on the winter tires squirming.

amen

I wouldn't bother with winter tires if I didn't deal with snow and ice.

pretty much amen. there might be some odd driving environment where at least a certain kind of winter tire might be much better than any all-season. i agree for our climes though; if we didn't have snow or ice, and just had the cold (if that could happen), then the benefit of winter tires would be greatly diminished, especially since you have to change them, store them, etc.

tankinbeans wrote:Letting air out won't net appreciably better grip strength? I'm speaking specifically winter since my winter tires have never been brilliant, thus my wondering if I'm using them wrong.

i thought you're supposed to overinflate them to help narrow the contact patch and do other magical stuff.

potownrob wrote:im gonna do a similar but more real-life test tomorrow. gonna see if my all-seasons can run in the snow. never changed over to the snows. may not have to. probably will...

epic fail

potownrob wrote:i thought you're supposed to overinflate them to help narrow the contact patch and do other magical stuff.

It doesn't narrow the contact patch (unless you go to ridiculous levels like 200psi), it shortens the contact patch, whose width will remain the same as tread width but total area will reduce. That magical stuff is great for fuel economy, treadwear life, road hazard resistance, dry pavement cornering traction (because stiffer sidewalls; may not help with some tires/sizes/cars), and various other stuffs. Snow and ice are whole other beasts with very different needs.

tankinbeans wrote:Letting air out won't net appreciably better grip strength? I'm speaking specifically winter since my winter tires have never been brilliant, thus my wondering if I'm using them wrong.

If you overinflate (beyond car label, but not necessarily beyond tire's max rating) like I do then you may or may not have some improvements in snow and even on wet pavement by reducing that inflation. This is absolutely a situation that calls for experimentation to be done somewhat regularly, especially any time there is a change in tires or car. Again, just remember that the label on the car is the minimum pressure that's sure to be safe (with car loaded to GVWR in hot weather at maximum speed expected by engineers with tires not excessively aged or damaged). Any less and you risk highway blowouts (plus less resistance to road hazards and such).

On my pickup with load range E tires (rated up to 80psi), there is wet/slush/shallow snow traction to be gained by backing the rears off to 50psi when the bed is empty. In deep snow I guess it's more about treads biting and engaging snow and contact (with snow) patch is huge no matter what; and on sheet ice there's nothing short of studs that matters. Anyway for wet/slush/shallow snow, contact patch becomes too small and tire too hard at 70+ with so little weight on it; and when it's like that there's little to gain from higher pressure anyway. The idea is to cut through the h2o and make as much pavement contact as possible, and if the tread is doing its job then that happens easily and you want more contact patch touching pavement.

Elsewhere I haven't usually found major gains by backing off the pressure, but that doesn't mean you won't. My earlier reply was addressing it as a question of "can I experiment with this to see if it helps" rather than "will this help".