Winter Tires.

& to many “Winter” ties thread.. i posted this in other one other day. Interesting read.

 

I hope that keeps up given the El Nino year. Planning to visit that area in April hopefully for skiing.

 

Finally a new ice traction rating and symbol to add to the acceleration snow flake on winter tires

https://www.caranddriver.com/news/a45861084/winter-tires-new-ice-rating-certification/

 

wonder why they only do the test at 12-15mph. Seems not very useful vs real life driving.

 

Interesting. The article failed to quantify what performance level is required to achieve the "ice" certification though.

 

Again not try’n to beat DeadHorse.. Different Strokes for Different Folks.. my use is different than others. Im jus giving my 2cents.. & Real World “Experience”

 

In most test i have seen (tirerack etc) its done on an indoor ice rink. Any faster and they wont be able to get up to speed and brake in the distance available. And speed is Irrelevant in this test. If it can stop 18%+ better at 15 it will do the same at higher speed.

 

18% or shorter braking distance from 12-15 mph than reference tire. Its all there

 

My Nokian R5 winter tires are going on this Friday . Looking forward to the snow and ice in the okanagan! Bring it on

 

Excellent. Seems nokian was the first to include this new certification. Sure others will follow soon. They probably already meet it but just haven't done the required test yet.

 

oh that makes sense about the ice rink - just seems like a longer test on a lake or something would give more accurate results. Also, +18% vs 3PMS is kind of disappointing. Should be way more than that, like 50 or 100% better to really mean something. I feel like this is more of an ISO testing revenue stream than a useful spec.

 

Its like the snowflake symbol where anything 10% or more gets it .For this new test anything over 18% better gets it. I agree that it would be nice if it was rated the same as treadwear where the number get larger based on comparison to a reference tire.
One is just acceleration on medium packed snow. The other braking on ice. Totally separate tests. One is more dependent on tread pattern, the other tread compound and sipping. Thus you can have one tire better than another in acceleration and the another better in ice braking. Better in one doesn't equal better in the other.

And from basic high school physics the coefficient of sliding/kinetic friction is not dependent on speed. So if its 18% at 15 mph its 18% at 60 assuming the surface is the same and its much easier to maintain the same surface in an ice rink than a lake.

"The coefficient of kinetic friction does not change depending on the relative speed of the two objects. The coefficient of kinetic friction depends only on the types of surfaces in contact."

 

sure, but the error in measuring 18% of 5ft of stopping is worse than the error in 50ft of stopping.

 

The error on an ice rink will be less than on a frozen lake surface . Surface consistency matters since "The coefficient of kinetic friction depends only on the types of surfaces in contact. And during the test they do it 9 times and remove the highest and lowest to minimize error.


And i agree that for those that only respond to BIG numbers the difference in braking distance at 30MPH and even 60MPH would be impressive.

Based on kinetic energy the distance at 30MPH would be 4X than at 15 and the distance at 60MPH would be 16X.


Reminds me of an issue that someone who just bought his first car with ABS. He complained to the mechanic that it wasn't working properly at low speeds. He told them it stopped working around 3-5 MPH. They had to remind him that ABS prevents the wheels from stopping and if it didn't disengage at those speeds he wouldn't stop either.

Even though it happened over two years ago I am still amazed that only 6 people died in the ice induced pileup in texas. Cant imagine being at the back and seeing a semi trailer just about to slam into you

https://www.youtube.com/watch?v=els9-NM6SIM

 

@babylon5 a stark reminder to be safety oriented in bad weather. The appropriate tires and slower speeds. Thank you for taking the time to post.

 

& clean the Snow off your Vehicle, & drive accordingly..

 

Anyone have experience with the blizzak dmv or lt tire? So there is a national backorder I guess for the michelin x-ice snow I was going to order.

Reviews say dmv is better all around(mainly in mud/deep snow) vs the LT is better on ice(stops 11ft shorter). Wondering if anyone has used each and their opinions.

 

No experience but notice the LT has "Utilizing a rugged, light truck winter compound" where as the DMV uses their "Bridgestone's adaptive NanoPro Tech Multicell compound that features a water-loving hydrophilic coating and microscopic bite particles"
So what makes normal blizzaks well know isn;t used on the LT. Some posters mention the LT's also pick up rocks like crazy.

 

LT tires are usually much more firm and perform worse on ice, especially on light weight trucks.

I'm surprised there's any suggestion it out performs the DMV2.

I always specifically buy SL tires so they are as soft as possible for ice