Aspect ratio and winter traction

Gentlemen, again talk is cheap if you are so sure we can easily test this.

 

Blue T, at home, posting to TacomaWorld

 

The are the test Facts:
http://www.tirerack.com/winter/tech/techpage.jsp?techid=126

http://www.fourwheeler.com/how-to/wheels-tires/1502-snow-tire-tech-traction-for-the-winter/

http://www.tirereview.com/breaking-winter-tires/

 

Clearly, everyone running skinny tires in the snow just have magical tires with unicorn fur woven into the rubber so they handle well.

Also, I've never had any issues breaking traction on hills or accelerating onto the highway and I've never been stuck. Skinny tires have worked for me for years, not even you can argue that. Troll on

 

I can't explain why your stupid question is stupid.
I can buy any size tire that will fit my car. Lack of wider tires for bicycles is not my issue. I dont have problems buying wider tires for my vehicle, if it fits they manufacture the size.
Maybe you should stop shopping at Walmart for the bicycle tires.

 

My friend who lives in Central NJ claims he drives every winter on bold all season tires while people buy Winter tires.
Where he lives it snows like a inch, while its 34 F outside. So low amount of snow, and temperature above freezing so no ice forming on the road. Thats the only time where skinny tire will give any benefit, Now he considers inch of snow a winter driving, I consider fall driving. See the difference. No Unicorns, just city folk driving skinny tires on well plowed clean roads and claiming its true winter driving.

 

Think of it like this- air down from 30psi to 15psi. If At 30psi there was a contact patch of 6sq inches, at 15psi the contact patch will have an area of 12sq inches. Obviously, that's idealized, but I think that's the point.

For a 32psi tire, the contact patch will grow by 1sq inch (total for 4 tires) for every pound added to the vehicle.

 

Specific to the OP's question about traction on icy/compacted snow roads (versus deep, untracked snow)
not sure if tire compound, and temperature has already been mentioned, but a designed for winter tire uses compounds that stay flexible at low temperatures. The siping, tire compound composition, and tread pattern design (usually quite small gaps between tread blocks) is what will give you the traction in the OP's area of concern, to squirm and squeeze out the water and get any kind of grip on the surface with all the little edges the siping pattern create. If you are still having difficulty, yes, lowering your air pressure from the standard day-day rating will help with both the contact patch area and the amount of 'squirm' /flexibility the tire will have on the surface to gain traction. The change in contact patch area will be mostly determined by the aspect ratio, and of course air pressure. A low profile tire (65,60, to 45 series) tire will not give you much increase in the patch area as you lower air pressure, but a 70-85 series aspect ratio with its taller sidewall will. On sheer ice, chains/studs will have the advantage, every time.

For deep snow, yes, a narrow tire with aggressive tread pattern will help you bite through to the base, and provide less resistance against the snow. Once the snow depth reaches your bumper height, however the amount of resistance against your undercarriage will exceed the available friction from the tires-surface contact, and you also loose contact pressure - you get stuck. A taller tire can help increase the ground clearance (allowing you to go further into deeper snow to get stuck.) For really deep snow, that has been compacted - say by snowmobile tracks, or wind & weather, then a wide, low contact pressure, will allow your vehicle to float on top of the packed snow. This is what the Icelandic trucks rely on, because they are driving on top of several feet of snow.

How do I know? I'm one of the folks that gets called out to get people out of trouble when they get stuck in the winter on backroads, in their ill prepared vehicles. About 50% of the time, we're able to get their vehicle out as well adapting to their conditions, using various techniques, the biggest gain being getting all that snow jammed up on the bottom of their vehicle out.

 

PS If I were to choose a winter tire for the family car to get around town, to the ski hill, and across mountain passes (read: usually plowed roads) it is going to be an ice radial winter tire, of the correct size for the car, and a narrower one if available, without significantly changing my ground clearance (ie narrower but taller profile)

For the truck heading out on unplowed backroads, a taller narrow winter tire, with more open blocks, that I can lower the air pressure in to increase the contact patch, when conditions deem appropriate.

 

Ah yes, sorry aboot that bringing in sane logic here, My Bad, not sure what I was thinking. Carry on, and i'll excuse myself, after all I have to leave a bit earlier so I have more time to drive on tonight's icy roads.

 

This logic only applies (as VE7OSR described below) when on compacted snow that a 5,000 lb+ truck can't sink into. The continental US does not have these conditions on public/paved highways (or even logging roads for the most part). The main key is, you want to increase the downward pressure on your tires' contact patch, to gain grip and maintain traction. Snow does not provide traction.

A 5000 lb truck, with a narrow tire, has more downward pressure on it's tires' contact patch because the load is distributed less. Grip and traction increases.

The same 5000 lb truck, with a wide tire, has less downward pressure on it's tires' contact patch because the load is distributed more. Grip and traction decreases.

This law of physics along with the tire's compound (maintains a supple tire) and tread design (cleans the contact area) gives the tire the ability to gain traction in freezing temps and slick conditions.

 

Good for your friend... I do a lot of driving well north of Jersey and I'm usually on the roads in the morning before they're plowed because of my job. I seem to remember getting a little more than a dusting last year and, shocking I know, the skinny tires did perfectly fine. I know we don't all live in the snow mecca that is CT, but there are some other areas that get snow.

 

for studless road-going mountain snowflake tires
everything is right except this part about cleaning the contact area

the large grooves are designed to push away slush or water yes,
but the smaller grooves and sipes actually designed to capture snow.
Snow tires give you greater traction while holding a little bit of snow.
the small ice crystals increase friction. Even ice requires force (friction)
to move along other ice particles. there would be more friction with your tire
covered in snow than the tire itself.

notice the most advanced snow tire technology today, and how well snow
sticks to the tire and does not shed from the sipes

 

Can you provide documentation on this?

 

And my Friend drives around NJ on half bold all season tires.... So what your point?
If you still think your skinny tires can get through the level of ice, I told you we can easily test this. I am calling your story complete BS. Prove it.
If 700 HP Rally car on 3 inch wide skinny tires equipped with studs can not get through ice and packed snow, your truck with 6 inch tires will not for sure.
So either your driving on mostly plowed roads, what makes your "winter" driving experience null. Or you a full of shit.
So sorry with out video proof of your skinny tires getting down to whats underneath the snow this is complete BS.

You do realize that winter tire in the picture is wide tire (easily almost 7 inches wide which is probably maximum width for passenger car with out modifications) and not 3-5 Inch skinny tire ?

 

bold tires are the best tires. Nothing can stop them.

 

the thermodynamics of the phase of the solid gas interface


Were is the temperature, the pressure, the thickness of (l) corresponding
to the number or particles in this case. and are the atomic density and the
chemical potential in (l) and .

so the derivation to results in:



I have to quit the thread because arguing with idiots and trolls is impossible

td;dr : snow sticks to snow

 

I think its a NJ thing, bold tires seems to be common in there. Than again they dont get a lot of bad weather.

 

127.0.0.1 is Blue T
Blue T is 127.0.0.1