On ice like on asphalt: premium winter studded tyres

Laurels of the top winter studded tyres in the model range of the Finnish brand Nokian are deservedly given to models with the index Nokian Hakkapeliitta 9 225/45 R17 94T . However, the "Nordic seven" is not so far behind its older brother in terms of characteristics and driving qualities.

A special pinching technology, along with a well-organized tread pattern, gives the tyre excellent traction properties when moving both on icy surfaces and on loose or rolled snow. The spikes are inserted vertically into the tread blocks and are supported in this position by means of so-called "bear claws". At the base of each of the claws, shock-absorbing Air Claw holes are made, aimed at mitigating the impact of spikes on the roadbed and reducing noise when moving.

The wide side of the spikes are perpendicular to the direction of movement, which helps to increase their contact with the road surface during acceleration and braking. When manoeuvring, the angular faces of the spikes are included in the work. In addition, the tread blocks are permeated with a great variety of lamellae that increase responsiveness in driving on dry and snowy roads.

The degree of tyre wear can be monitored visually by relying on two types of indicators: the snowflake icon and the three digits (8, 6 and 4). The disappearance of the first symbol signals the onset of a critical moment when the tyre becomes unsafe to operate, and the digital symbols suggest the current tread depth in millimetres. The Nokian Nordman 7 is available in a variety of sizes from R13 to R18, and the "delicious" price tag of the tyre (as for a representative of the above-average rubber class) increases its attractiveness in the eyes of potential buyers.

The French company Michelin has no experience in the production of winter tyres. An example of one of the most technologically savvy products of the brand is the studded tyre X-Ice North 3.

When creating a tyre, a thermoactive rubber mixture is used: in warm weather, the inner layer of the tyre softens, hiding the spikes in the tread depth, and when the mercury thermometer column is lowered, the rubber becomes stiff, exposing the spikes and ensuring their strong grip with ice. This design minimizes the negative impact of spikes on asphalt surfaces when moving along them at plus temperature.

Technological holes are made around each of the spikes, which serve to remove ice chips from the contact spot. As a result, the efficiency of the tyre increases, and the probability of losing the spike decreases. The risk of falling out of "steel claws" is also reduced due to the special conical shape of the spikes.

The directional central part of the tread pattern is complemented by powerful shoulder zones, which give more confidence when getting into a rut or driving through deep snow. Equally important is the adaptation of the tyre to the not the best condition of east european roads — reinforced sidewalls distribute the energy of a possible impact over a larger area, reducing the likelihood of a cut or breakdown of the wheel. The owners of the model are not happy only with excessive noise on asphalt surfaces, but it is not worth focus on this disadvantage, since it is more or less found in all representatives of the class of studded winter tyres.

The standards of the Scandinavian countries, where they know firsthand about harsh winters, have strict requirements for studded tyres. In particular, the number of spikes per running metre of the tyre is regulated (less than 50 pcs.). However, the "temperamental Italian" managed to circumvent these restrictions thanks to the use of patented double trapezoidal spikes.

The use of double spikes provides improved grip on slippery surfaces. When the car accelerates over the ice, the spike bites into the roadbed with sharp multidirectional edges, and when braking, it clings to the ice with a common plane of the carbide insert. By its effectiveness, the branded "claw" is equal to two spikes of the usual design.

The directional tread pattern of the tyre with a powerful central part is striped with numerous lamellae, which help to ensure predictable behavior of the tyre in the snow. During testing, Pirelli Ice Zero receives high scores in the disciplines of countering hydroplaning, braking on dry asphalt and handling on ice.

Unfortunately, the tyre could not do without any disadvantages at all. Due to the peculiarities of the tread pattern, it turned out to be noisy when moving on asphalt, there is also increased rolling resistance, which does not affect fuel consumption in the best way. But the tenacity of rubber for winter roads deserves the highest praise, so the negative sides of the model seem completely insignificant against the background of its driving qualities.

The second generation of studded rubber of the IceContact line is strikingly different from the ancestor of the series. Improvements in it affected almost everything that the German engineers of the Continental AG concern had a hand in.

The similarity with the predecessor can be traced only in the asymmetric tread pattern. However, the blocks in it have a completely different shape, and the number of spikes has almost doubled. Moreover, they were dispersed around the perimeter of the tyre in such a way that, upon contact with the road, each spike clung to a new section of ice. To prove that the increase in the number of spikes did not entail a greater destructive effect on the roadway, the tyre passed a number of additional certification tests.

The spikes are protected from the formation of ice by special pockets, which also have a positive effect on acoustic comfort when moving. In their landing place, the "steel claws" sit very firmly — their installation is carried out together with a small number of special personnel, which, during vulcanization, fixes the spike with a death grip in its position.

Returning to the topic of the asymmetry of the tread pattern, it should be noted that its inner part contributes to a more confident overcoming of snow obstacles, and the outer part is responsible for the responsive behavior of the tyre on slippery roads. When manoeuvring on ice and snow, a clear reaction to taxiing is achieved, thanks to which the name Continental IceContact 2 is associated with the guarantee of confident handling on winter roads.

The studded rubber of the Hakkapeliitta line from the Finnish brand Nokian is rightfully considered one of the best solutions for driving on snow-covered or uncleaned winter roads. The ninth generation of the series is "finished" almost to the technological perfect and provides stability on a slippery roadbed, comparable to that of summer tyres when riding them on dry asphalt.

The secret of the tyre's tenacity for icy coatings lies in the use of different types of spikes: "the claws in the central part of the tread are responsible for longitudinal traction, and in the shoulder areas — for transverse. Simply put, the spikes in the centre improve acceleration and braking characteristics, and on the sides — keep the car on the road in turns. At the same time, the special shape of the spikes minimizes the risk of their loss on difficult road sections.

The central part of the directional pattern of the tyre tread is formed by two rows of blocks. Some of them are connected to the central edge, while others are located slightly to the side, which forms a complex geometry of channels for more efficient removal of water and snowmelt masses from the contact spot. Snow Grip Boosters and Deep Grip Boosters also give you confidence when moving through the snow.

The sidewalls of the Nokian Hakkapeliitta 9 are reinforced with aramid fibers. Their use allows you to overcome various obstacles (for example, curbs) without fear of cutting the tyre and without the risk of bumps on it. Special attention is paid to the wear indicators: the snowflake symbol and a set of numbers 8, 6 and 4, which are erased as the tyre wears to the appropriate tread depth (in millimetres). Such a rich load of advanced technologies is slightly overshadowed only by the high cost of the tyre, but it is excusable to be the best among the best representatives of winter tyres.