Snow has a strong affinity for itself, meaning snowflakes naturally tend to bond together with a strength that varies depending on temperature and humidity. It can be said that the lower the temperature, the more the flakes tend to crystallize, turning into ice. An example of this is the so-called “powder snow,” typical of cold and dry Arctic climates. It consists of frozen flakes that, once on the ground, tend to remain separated from each other. Conversely, the so-called “wet snow” occurs in winter in temperate regions when the temperature approaches zero degrees Celsius and the air humidity is high. In this case, the flakes become heavy and, upon touching the ground, tend to adhere to each other, creating a uniform layer that becomes denser as the humidity of each flake increases.
Regardless of its strength, the adhesive force of snowflakes is the basis of phenomena such as the so-called “snowball effect” — the increase in mass and volume that a block of snow undergoes when rolling downhill on a snowy slope — as well as avalanches. This significant characteristic was exploited starting in the 1970s by tire manufacturers to develop winter tires capable of stabilizing and controlling vehicle trajectories without the need for studded tires, which were common at the time. This led to the creation of the first so-called “siped” tires, where the tread blocks featured thin grooves that opened and closed during rolling, trapping small amounts of snow that adhered to the snow on the road surface. The mechanical traction exerted by the tread blocks is further enhanced by the use of high-silica compounds, which maintain elasticity and grip even at low temperatures, unlike “summer” compounds that harden below a certain temperature, reducing traction.
Special compounds for cold climates
Once it was confirmed that siped tires met their objectives and were appreciated by the market, the same construction principles were applied first to tires for medium and heavy commercial vehicles and now, thanks to BKT, to agricultural machinery. These tires are specially designed for tractors that need to handle winter road maintenance or road hauling on frequently snow-covered roads or in conditions where temperatures fall below six to seven degrees Celsius — the range that typically challenges non-winter tires.
Called “RideMax Frost,” Bkt’s siped tires expand the company’s offerings with a highly professional and innovative product. This confirms Bkt’s commitment to providing not only versatile product lines but also specific solutions tailored to precise operational needs. Structurally, the new tires feature a radial construction supporting an asymmetrical, directional tread design with an obligatory rotation direction. The tread has an aggressive block pattern that creates numerous deep grooves, ensuring effective self-cleaning when the tire rolls over muddy surfaces. The blocks are also arranged to provide a uniform footprint between the center and the sides, with zigzag sipes that trap as much snow as possible to exploit the snow-snow friction coefficient, which is higher than the snow-rubber friction coefficient.
Excellent performance on cold asphalt
Siped and thermal tires perform better than summer tires not only on snow but also on wet or dry asphalt at temperatures below six to seven degrees Celsius. This is because the tires heat up as they roll on asphalt, hence the term “thermal,” maintaining the elasticity of the specially designed compound. The sipes also contribute to this effect, as their continuous movements generate heat even in the absence of snow. The result is superior road grip, shorter braking distances, and improved comfort due to reduced noise and vibrations compared to traditional studded tires.
Title: “RideMax Frost” tires by Bkt: the snowball effect
Translation with ChatGPT
