Aspect ratio and winter traction

And if your property is on the wrong end of a snowmobile track? Then what... then you drive on a snowmobile track.
Or what if you have a snowmobile that is BROKEN on the wrong end of a snowmobile track? Same thing, you're going to get it.
End of story.

 

this this exactly this.

skinnier tire digs in more

fat tires float

if you had studded bicycle wheels and tires as wheels you'd be completely unstoppable

so, when opting for winter wheels skinnier is better


my friggin yaris is crazy good on any wheel that has a snow tire on it, but I have a two sets, stock...and a smaller set
with the same winter tire model michelin x-ices, (just 1 inch narrower) and it is noticeable when the little wheels are on ....it is beast-mode

 

This thread is hilarious. I just read through all 5 pages and I'm

for more.

 

So decide if the type of driving you will be doing most will benefit more from floating above the snow or digging down into it. Are you driving on 3 feet of packed snow? Then you want flotation because if it digs in, you're stuck until spring. Or are you driving on 3 INCHES of packed snow? Then you want to sink down to the hard surface that you can grip on.

 

Unfortunate thing about "common" sense, is that it is rare that it is actually correct. Some things are best left to physicists than the common folk. While the balance of your statement sure makes "common" sense, it is actually entirely incorrect.

There are TWO forces at play, and you are only accounting for ONE of them.
You are thinking only of the rotational force that is trying to accelerate the vehicle, but you are forgetting about the force of GRAVITY.

So lets try to look at this from a slightly different angle. You say that snow is slippery, right? I totally agree. This is the reason why you want to get your tire up against the asphalt that lies UNDER the snow. Because asphalt is a much better (high traction) surface for holding off the rotational force being applied from the vehicle's wheel. The greater the surface area of the tire, the more it will float your tire above the asphalt, leaving its traction surface mostly snow. A skinny tire will allow the force of gravity to pull the vehicle down closer to the asphalt, giving you a greater traction.

Snow is SO slippery, in fact, that 2 square inches in contact with snow will yield less traction than 1 square inch in contact with asphalt.

"But but but... the snow is going to hold you up off the asphalt no matter what!!!!"
Not so. Winter conditions are quite varied. There is this wet gooey stuff called "slush". Its thicker than water and will hold you up a "bit", but thin and fluid enough for you to find your way to the bottom of it when your equipment is appropriate.

Q: Why do racing cars use different tires in the rain?
A: To get the layer of water out from between the rubber and the asphalt. The loss in surface area yields greater traction in wet conditions than the greater surface area yielded by the slick.

But only IF you are operating on a *high traction surface*.

 

Who said anything about running at the same pressure?

 

When you're talking about the effects of changing one variable, you assume all others are kept the same. Otherwise you can't say what gave you the results.

 

Air pressure is a variable though. Whatever the tire size is that you are running, you make your comparison *after* optimizing the air pressure.

 

Are you in the sciences field?

 

here is another thing about winter traction (all other things being equal, and no metal studs)

snow tires that hold onto snow and keep it in the grooves (like michelin x-ice)
grip better than larger lugs that don't get packed with snow

tire engineers realized back when the blizzak was developed that the only thing
that truly grips snow best, is more snow. that is why modern snow tires have
closely spaced and extremely siped blocks....with some nice rain or water grooves in the middle
to deal with the puddles....a part of that design is to hang into as much snow as possible in the tread, as it grips best.

extreme siping is for gripping ice
closely spaced blocks is to hold onto snow, to grip more snow
center grooves are for water extraction for puddles

and if you can add studs that certainly helps on ice


there are a ton of variables and 55 different types of ice and snow
but -in general purpose winter driving- the above is always true

 

I think his point may be this. Your sketch implies that a shorter tire would have a longer contact patch then a taller one with equivalent pressures. Which isn't necessarily true. A narrower tire has a longer patch than a wider tire at equivalent pressures and diameters.

 

No, my sketch referenced WIDTHS. 245 and 265 are widths not heights. I agree with your last statement though.

 

You only need wide for floatation in snow deeper than your frame and then some. And guess what. No 285 or 315 is going to hold your truck above the snow.

Wide tires are for people who prioritize looks over performance haha.

 

That depends on the snow.
One of my old trucks had 10.5's (roughly 265's), and on hardpack (groomed snowmobile trails), it would float, not get stuck... most of the time.

Also, your assertion that it is only beneficial for snow "deeper than your frame" is incorrect. If you had ever been stuck in the snow, you'd know that it takes a heck of a lot less than hanging it up on your frame to get stuck in. All it takes is 4 little divots for your wheels to sink into, without enough traction to climb out from. Remember that snow/ice is slippery.

 

Yeah, man. I've been in the snow a whole lot. And I spend every single winter volunteering to pull people out of the snow after every single blizzard haha.

BUT, this isn't about your or my little experiences here or there. I've admitted room for exceptions depending on circumstances in a previous post. But you know what, at the end of the day, you can like your fatties and I'll like me some skinnies (and I'll be more than happy to come pull you out of a ditch).

 

This whole thing went to shit.

 

Mixing ignorance and facts always makes a shit stew here.

 

^^^^
My new favourite saying

 

I think bottom line is if narrow tires worked for you and you think they ok with you that means your environemnt is not that bad and you can use narrow tires.
but narrow tires never where better for the snow driving, thats why nobody who drives on real snow (including Icelander trucks that drive on snow and ice) use narrow tires.
Now I understand somebody had seen Rally car on skinny tires but what they missed were studs in those tires. The big difference is that studs made out of steel can penetrate frozen ice while rubber can not. And if you driving in winter, 90% of the time under that snow there is ice. Studded tires vs rubber tires, it's apples to oranges.

If you driving on rubber, than biggest patch with most edges is what you want. And that is a fact.