Winter tires for VW Polo 9N:-(

Hello,

Yesterday, my new tires (195 series Uniroyal MS 55 Plus) were quite disappointing.

On a lightly trafficked, yet not cleared, country road with a 5% incline, there was approximately 10 cm of damp snow.
While I didn't get stuck, but at 4th gear and approximately 50 km/h (31 mph) = 1250 rpm, I couldn't give it even a little bit more gas, or the tires would spin – despite the PD torque deficiency at low RPMs.

The road surface was barely noticeable, and the slope of the road towards the ditch required me to occasionally correct with a full hand's width of steering correction to the left in order to drive straight.

Instinctively, I think my old Golf 3 would have handled much better with those 7-year-old (!) 175mm Fulda Gravito tires.
The impression of "no problem" was confirmed to me by the buyer of my car, who was also driving around yesterday – with approximately 4mm of tread remaining!

And that's what people generally say: technological progress is constantly improving the quality of webcams -> Nonsense, yesterday it seemed quite the opposite to me.


Does anyone here have an explanation for this?
Could it be due to the 2 cm wider tires, even though the Polo is about 100 kg heavier than the Golf, and that extra weight likely puts more stress on the front axle (6-speed transmission, larger brakes, thicker drive shafts...)?

Or are winter tires now only being optimized for comfort and similar minor aspects, while their actual winter performance has already been maximized?

I have also spent a long time researching the topic of the "ideal tire." What seems interesting to me is that there isn't one.
Based on the reports I've read, a tire size like 155/70 R13 received excellent ratings, while another size, such as 175/70 13, only received a passing grade. As has been discussed before, not every tire works well with every car. I've now decided on an all-season tire, the Goodyear Vector 5. It does have some drawbacks compared to a summer tire in dry conditions, but it performs better than a winter tire. Yesterday, I was quite satisfied with its grip on snow. I also had satisfactory results with the Vredestein Snowtrac II.
Perhaps the road under the snow was icy where you were. All tires perform almost equally poorly on ice. From my experience, I've always found that narrower tires provide better traction in snow. Rally cars also use relatively narrow tires for driving on snow (or sand) compared to racing cars designed for asphalt.

And that's what people generally say: technological progress is constantly improving the quality of webcams -> Nonsense, yesterday it seemed quite the opposite to me.


Does anyone here have an explanation for this?
Could it be due to the 2 cm wider tires, even though the Polo is about 100 kg heavier than the Golf, and that extra weight likely puts more stress on the front axle (6-speed transmission, larger brakes, thicker drive shafts...)?

Or are winter tires only being optimized for comfort and similar minor aspects, while their actual winter performance characteristics have already been maximized for quite some time? }

Haha, I had the exact same experience testing it out in the snow-covered Allgäu region yesterday. Last year, our Mercedes had Conti TS770 tires. This year, I got a set of TS790s with the same dimensions because the old tires, even though they were only 5 years old (with 5mm of tread), offered very little grip, and that's not fun with 280 horsepower.

Where the 770 models exhibited a tendency to strong understeer, the 790 strictly followed steering input. The 770 consistently had problems starting on even slight inclines (with the traction control system working constantly), while the 790 started easily and the traction control system rarely engaged.
The 790 is also generally better than a new 770. I've noticed a significant improvement here, as a gasoline-powered bike isn't really designed for winter conditions and doesn't handle snow particularly well.

In my opinion, Uniroyal doesn't produce top-of-the-line winter tires; they are more geared towards the budget sector, and perhaps that's where the problem lies. The question is also whether a silica compound is used in these tires, as this is often not included in cheaper tires.

Is there a triangle with a snowflake symbol on the tire sidewall? If so, it should be a genuine winter tire; the requirements for the M&S marking are extremely low and are sometimes even met by summer tires.

Are the tires already properly worn in, and has the silicone protective layer and the rubber tabs been completely worn off?

Does your engine also have ASR/EDS? If so, could the EDS system have caused understeer during operation?

Okay, I've checked again. In physics, the coefficient of friction is independent of the surface area. So, whether you have narrow or wide tires initially doesn't matter for grip; it only depends on the coefficient of friction (µ). However, with snow, the larger surface area of the tire acts like a windbreak and counteracts acceleration. The contact pressure is also different with wider versus narrower tires, and this appears to be relevant in snowy conditions. The smaller the force on the snow, the looser it remains, and the lower the grip. Therefore, wider tires are not as good as narrow tires in snow.
Your slightly higher weight is offset by the wider tires, because pressure force equals pressure multiplied by area.

Well, the contact patch area is always the same for common tire sizes. It's about the size of a postcard.

With narrower tires, the long side of the tire is parallel to the direction of travel, while with wider tires, it's perpendicular. The contact area is almost always the same. Wider tires generally offer slightly more lateral grip during cornering, while narrower tires provide better traction in deep snow because the tire has 'less' snow to compress.

If the contact pressure is always the same and the contact area is also the same, then a wider tire should compact the snow in the same way as a narrower tire, so it shouldn't make any difference, right?
It is undeniable that wider tires have a different handling characteristic than narrower ones. This is because narrow tires tend to "bite" more effectively when cornering compared to wider tires. Therefore, narrow tires with a relatively high aspect ratio (ratio of tire height to width) also feel less stable.

I think it depends more on the tire itself than on its width, at least if it's not excessive. 255-width winter tires are nonsense .

I was able to convince myself of the quality of Maloya winter tires based on several cars. Last year, on my mother's Golf, they had very good performance both without snow (wet/dry) and with snow! The following year, she didn't get Maloyas anymore but some 'brand-name' tires (Fulda, Fredestein, I don't remember exactly ).
'These things were significantly worse to drive in every aspect! That's why we (including me for my new Leon) have already ordered Maloya tires for this year, even in the summer!'
The Golf has tires of size 195/xx-15, and mine (due to the larger brakes / space between the rim and brake caliper) have 205/55-16. I'm extremely happy with them. In dry conditions, they are naturally a bit worse than summer tires, but in wet conditions, there is hardly any noticeable difference. And they perform great in snow, providing excellent grip and feedback.
'Regarding liability in snow or slush, no differences can be observed between the various tire widths.'

Julian wrote:

In my opinion, Uniroyal doesn't produce top-of-the-line winter tires; rather, they are geared towards the low-budget sector, and perhaps that is where the problem lies. The question is also whether a silica compound is used here, as this is often not included in cheaper tires.

Well, the price range is comparable to the (subjectively) better older Fulda tires on the G 3.

My online research before purchasing the WR tires indicated that the Uniroyal tires already contained a silica compound.
The Fuldas from 1997 definitely didn't have...

Quote:

Is there a triangle with a snowflake depicted on the tire sidewall? If so, it should be a proper winter tire; the requirement for the M&S marking is extremely low and is sometimes already met by summer tires.

Snowflake, yes, but inside a circle.

Quote:

Are the tires already properly worn in, and is the silicone protective layer and the rubber tassels completely worn off?

Estimated mileage: 1000 to 1500 km since purchase. The rubber wear indicators have been gone for a long time (except for those in the tread grooves), as I brake less before curves and take them at a significantly faster speed than average.

Quote:

Does your engine also have ASR/EDS?

If so, could the EDS system have caused the understeer? }
I canceled the ESP (Electronic Stability Program) and only have ABS (Anti-lock Braking System) on board.
"Interestingly, brake tests (with active ABS) gave me a better understanding of the tires than their traction and lateral grip ratings."

According to the ADAC test report, the Uniroyal Plus 5 also exhibits some weaknesses in snowy conditions and has a high rate of wear.
Braking performance on snow: 2.5 (out of a possible score).
Starting price: 2.3.
The really good ones here have scores significantly below 2.
Vector 5
Braking on snow: 1.7.
Starting price: 2.3.
And that's for an all-season tire. So why bother changing them at all?

wutz wrote:

According to the ADAC test report, the Uniroyal Plus 5... and also has a high level of wear.

Let's see, then I might have to replace them soon (with something better) .

I'm driving on a Dunlop Wintersport tire in size 195/65 R15.

I probably lack experience with high-quality winter tires because I used to drive an old, generic Passat – always with the typical loud humming noise starting at around 80 km/h.

However: It's extremely quiet, performs very well in snow, and in my personal opinion, it doesn't have any weaknesses anywhere else either – all at an acceptable price.

For those who are interested: I recommend him - the ADAC also does .

Happy New Year!
Herwig.

Hi,

If we only consider the contact area between the tire and the road surface, then a general rule of thumb is: the wider the tire, the better.
Reason:

Frictional force = coefficient * area * force.

The product of 'area * force' is constant for a car, but the coefficient increases with the contact area.

So far so good on solid surfaces (ice, packed snow, dry/wet asphalt). However: A wide tire has a huge problem in slush and wet conditions: The water needs to be moved much further, and more water needs to be transported for the tire to make contact. In addition, there's the previously mentioned issue: surface pressure. The tire is supposed to compress loose snow, and then the individual tread blocks grip into this relatively firm surface.
Therefore, the goal is to find a compromise between high friction and easy displacement of water/slush.
Don't forget that using 225 tires in the winter always makes the sides of the car incredibly dirty...


Best regards,
Sure, here is the translation of the text from German to English:

'Micha'

Hi,

When I compare the Pirellis on my Golf to the CEAT tires on my wife's Lupo... it's a clear win for Pirelli. By the way, CEAT is actually a subsidiary of Pirelli.
"On wet roads, I almost had a scare with the CEAT tires, but they perform well on snow. The Pirelli tire is very balanced, performing well both on snowy and wet surfaces."
Yesterday, I drove up the mountain near my house, and the neighbors were staring blankly... I have no idea why. Later, I found out that I was the first person to make it all the way up the mountain. Everyone else had given up at the point where I started driving.

Buying tires is unfortunately a gamble. Only a few tire manufacturers will refund your money if you are not satisfied. And that's how you end up having to live with a bad choice for the entire lifespan of the tires.

I've had my new tires on for about a week now, specifically the Continental TS 780 in size 185. I'm really impressed with these tires!

Regarding all the discussions about tire width, it's important not to get bogged down in attempts to explain everything using Coulomb friction; that doesn't fully account for the phenomenon because interlocking effects also play a role.

If the contact pressure is always the same, and if the contact area were also the same, then a wider tire would compress the snow equally to a narrower tire, and therefore it shouldn't make any difference, right?


Cognitive bias: Consider how much wider the side of a tire is that needs to be compressed, for example, comparing a 225-width tire to a 175-width tire. The longer edge is roughly 22.5 cm versus 17.5 cm. In terms of contact area, the two tires are almost identical.
That's why, when driving on deep snow, it's always best to use the narrowest possible tires to prevent them from 'floating' on top of the snow, as this reduces the amount of snow that needs to be compressed by the tire. (Think about pushing a broom handle across water horizontally versus vertically...which is easier?)

On packed snow, a wider tire might offer slightly better tracking, but I've never personally experienced or noticed this in practice.

Calculating the coefficient of friction isn't that simple; the tire engages with the snow mass, and that engagement is a product of the positive/negative aspect ratio in the tread pattern and its structure. Unfortunately, it's not that straightforward.

Well, I think it's difficult to make a precise statement on this topic. There are too many parameters that aren't under control. We all have experience with winter tires, but factors like tire pressure, tire width, wear level, type of snow, outside temperature, distance traveled, and subjective impressions... there are just too many things that interfere with making a clear statement.

I have GT Radial 16'' winter tires on my Golf 205. They've never disappointed me in the winter. I was initially concerned that they might not perform well in snow, but with a gentle driving style, occasional ASR (Anti-Slip Regulation) activation, and adjusted speed, they actually feel quite good to drive. However, when braking on wet roads from higher speeds, I get the impression that they could be better. As I said, this is just my subjective opinion.