AVTOREVU 18 Date: (p. 8) Media Type: automobile magazine (Semimonthly) Distribution: Russia, CIS and Baltic states

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1 AVTOREVU 18 Date: (p. 8) Media Type: automobile magazine (Semimonthly) Distribution: Russia, CIS and Baltic states Test of studded tyres The comparative test of ten models of studded tyres: Nokian Hakkapeliitta 8 (#1), Continental ContiIceContact (#1), Gislaved Nord Frost 100 (#2), Pirelli Winter Ice Zero (#3), Michelin X-Ice North 2 (#4), Goodyear UltraGrip Ice Arctic (#5), Dunlop Ice Touch (#6), Bridgestone Ice Cruiser 7000 (#7), Hankook Winter i*pike (#7), and Kama Euro-519 (#8). Pirelli Winter Ice Zero (#3): Concerning the longitudinal ice dynamics, Pirelli tyres perform as affective as the test's leaders. Nevertheless, on the track sudden side skidding was detected. Pirelli tyres, be it winter of summer models, have always given a car sport characteristics. Similar performance was demonstrated on snow, but in this case grip was middle-level. Grip is good on asphalt - either dry or wet. The tyres' driving comfort is high, though they are too noisy. Those tyres can be suggested to those drivers who usually drive on urban streets cleaned from snow. Nokian Hakkapeliitta 8 (#1): ADVANTAGES: precise and timely reaction to steering and acceleration on snow; good braking on dry asphalt. DISADVANTAGES: the longest braking path on wet asphalt; stud noise in the cabin at every speed. Continental ContiIceContact (#1): ADVANTAGES: good grip on ice and snow; good controllability on ice and snow; high shock strength. DISADVANTAGES: low grip on wet asphalt; high noise level. Gislaved Nord Frost 100 (#2): ADVANTAGES: good grip and controllability on snow; minimal braking path on wet asphalt, low noise level, and hump absorption; DISADVANTAGES: moderate snow controllability. Pirelli Winter Ice Zero (#3): ADVANTAGES: traction (grip) performances on ice traction (grip) performances on dry and wet asphalt DISADVANTAGES: modest handling performance on ice and snow noisy

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3 One hundred and seventy, one hundred and eighty, one hundred and ninety Uncle Vanya was counting the studs on yet another tyre. Stop! What s the point of one hundred and ninety, if the Northern European countries where studs are still allowed introduced restrictions in July of this year? You can t have more than 50 studs per linear meter of tread! That means there shouldn t be more than 96 studs on a 16-inch tyre ()! We counted them again, and sure enough, the new Nokian Hakkapeliitta 8 tyres had 190 studs, or more than twice as many. Why did the Finns decide to get around the new rules, and does this number of studs give any advantage over competitors? We tried to figure it out during our latest comparison test of ten studded tyre models. The Scandinavian countries have been talking about tightening the rules for using studs for a long time now, because they cause increased pavement wear. Greens insist that asphalt dust is carcinogenic, i.e., causes cancer. A new standard of up to 50 studs per linear meter, regardless of the tread width or bore diameter of the tyre, was announced in However, the previous restrictions remained in effect: studs must not protrude more than 1.2 mm above the tread surface. What about safety? I mean, the more studs there are, the better the grip on ice, all other things being equal Tyre manufacturers found a loophole! It turns out you can insert more studs, but then you have to prove that denser studding won t increase the destructive effect on roads. As a result, a method for field tests of the effect of studded tyres on road surfaces was worked out at the Test World center in Finland. In a nutshell, after a certain number of runs on a granite slab, the weight of this slab should not decrease by more than after the same runs on reference tyres with the legal number of studs. However, there was no stampede to these tests afterwards. The people at Michelin, for example, decided it wasn t a very honest way of getting around the new restrictions, and threw themselves into perfecting tyres with fewer studs. The designers of the new Gislaved Nord Frost 100 tyres did the same. What about the others? The others went flat out to produce as many studded tyres as possible under the old rules (130 studs max for 16-inch tyres). That s because the ban that came into effect on July 1 covers production, but not sales of tyres with the wrong kind of studding! Only Nokian Tyres went its own way. The number of studs on new Hakkapeliitta 8 models didn t decrease, but actually increased by half. Of course, there was the test we mentioned, although as we learned, they didn t perform it at the Test World track, but at their own test center near the town of Nokia. This may have been supervised by an official observer from Trafi, the Finnish Transport Safety Agency. Competitors naturally raised hell, saying there s no way you can pass a test with that many studs! It s possible, says Mikko Liukkula, Development Manager at Nokian for studded tyres. in three years, we ve designed brand new lighter studs, performed dozens of tests on pavement wear, and we re convinced that our studs work just fine on ice. So, the main plot of the test is revealed. Photos: 1. White hell! Behind this fearsome sign is the winter test center of Nokian Tyres. But the test conditions are far from hellish. There are heated garages for changing tyres, and perfectly groomed ice and snow tracks. 2. There were 21 sets of winter tyres. First we ll compare studded tyres, and then in the next issue of AvtoRevu we ll publish the results of tests on studless tyres.

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6 Nokian Hakkapeliitta 8 + Grip on ice and snow Handling on ice and snow Braking properties on dry asphalt Grip on wet asphalt Noise High price Continental ContilceContact + Grip on ice and snow Handling on ice and snow Impact resistance Grip on wet asphalt Noise Overall score 9.0 Overall score 9.0 With this many studs, the win over the competitors, especially on ice tests, should have been resounding! But it was actually just a simple victory without a rout. They had the best time on the handling track, and make driving a joy. But their advantage over the ContilceContact tyres with 60 fewer studs was minimal, and the Continentals were even better in acceleration. That s because there are a lot of studs in the tread of the Finnish tyres, but they re small. The diameter and height of the studs and the width of the hard-alloy inserts are all less than on the Continentals. It s possible that at higher temperatures on soft ice, the small studs would have been more effective, but we performed our tests at 14 C. Nokian tyres are traditionally good on snow, with quick, precise responses to the steering wheel and gas. However, their performance on asphalt is mixed. The Nokians provide good deceleration on dry pavement, but they have the longest braking distance on wet pavement. The buzzing sound from the studs, which was always audible inside at any speed, was an expected weak point. 62 standard sizes are available, from 175/70 R13 to 255/35 R20) 94 (670 kg) Weight, kg 9.2 Tread pattern depth, mm 9.0 Shore tread rubber hardness, un. 48 Number of studs/stud lines 190/18 Stud protrusion, mm 1.2 Country of manufacture Finland Once again these tyres proved they deserved the name ContilceContact: they re outstanding on ice. Acceleration and braking were the best results in the test, and the balance of drift and skidding on the ice handling track made it feel like you were in an all-wheel drive, rather than a front-wheel drive car. Ease off the gas a bit on entering a turn, and drive the car into a curve with a controlled skid of all four wheels. They re also good on snow, and even tempt you to go too fast. All that prevented us from giving the highest score for steering reliability was a slight, not always appropriate tendency to a rear axle skid. Grip on asphalt is average, although they did very well in the moose test. The car responded sluggishly at first, but then the tyres clenched and held lateral Gs well. It s too bad the noise during these maneuvers was really annoying. On the straight, the Continentals whined fairly loudly; and in turns, the roaring intensified. But you don t have to worry about the safety of the studs. In order to yank out a glued-in stud, you have to exert a force time greater compare to the other tyres. Our crash tests also showed that the Continentals withstood the impact of hitting an obstacle well. Just the thing for Russian winters. Tread pattern depth, mm standard sizes are available, from 155/80 R13 to 245/40 R18) 94 (670 kg) Weight, kg 9.8 Shore tread rubber hardness, un. 49 Number of studs/stud lines 130/12 Stud protrusion, mm 1.3Country of manufacture Germany Photos: 1. Good studded tyres crunch ice into crumbs. The car was equipped with special scrapers to prevent the crumbs from interfering with the next rounds. 2. With the Audi 3 we could easily feel the difference between tyres. The stability control system was switched off and woke up only during braking and turning. 3. After testing each set of tyres, a sweeper drove on the ice handling track to clear the snow powder and make cuts on the ice using a roller made of tyres with long sports studs. Ice Uncle Vanya got behind the wheel of an Audi 3, and Andrei Mokhov got in on the right and opened his laptop after checking that the optical sensor was properly fastened. First, tens rounds of braking and accelerating, and then onto the hoist, change the tyres, and accelerate and brake again Even though acceleration was controlled by an anti-skid system, and deceleration by an ABS, the studs ground smooth ice into powder snow. We put the tenth and final set of studded tyres through the acceleration-braking test, and Sensational! The ContilceContact tyres had the shortest braking distance. They also gave the car the best acceleration performance. The advantage over the bristly Nokian Hakkapeliitta 8 tyres was very small, but it was there! That is, 190 studs lined up in 18 rows didn t work any better on ice than 130 studs in 12 rows. At least not at 14C. Why? Because the Finns actually had to change the design of the stud to reduce pavement damage. They re not only lighter, but also smaller in height and diameter than the studs used on the Continental tyres. And the ones used previously on the Nokian Hakkapeliitta 7. Plus hard-alloy inserts in small studs aren t that strong. The new (but still with 130 studs) Pirelli Winter Ice Zero tyres (AR No. 17, 2013) were right behind the two favorites.

7 Gislaved Nord Frost 100 tyres promise to be another outstanding newcomer this season. They have 96 legal studs, and provide very respectable braking on ice, although they were only eighth best in acceleration. Ahead were the familiar Goodyear UltraGrip Ice Arctic, Dunlop Ice Touch and Michelin X-lce North 2 tyres from last year s tests. So why did Michelin provide second-generation X-lce North tyres instead of the third generation? The company decided it would be better not to give these tyres to anyone for comparison tests before the official market launch of these new models. However, I still had a chance to do a quick comparison between the new Michelin studded tyres and competitors, and I ll tell you about it in one of the upcoming issues of AvtoRevu. Bridgestone also has produced new winter models, but the company also refused to provide them before the official premiere. We think it s because of Bridgestone Ice Cruiser 7000 tyres, which will also be heavily promoted on the market this winter. The Koreans were represented by the Hankook Winter i*pike, and Russians by the Kama Euro-519. Both of them showed very modest results on ice. But that s only about longitudinal grip. The handling evaluation started with turns on the ice track as fast at maximum speed and continued on the winding track, where both lap time and a subjective rating of comfort and steering reliability were considered. The Nokian Hakkapeliitta 8 tyres already won a resounding victory in these tests, with superb holding in turns and excellent control over the car on the track! I can definitely recommend these tyres for anyone involved in amateur ice races. They shave a couple of seconds off a lap, no problem! The Continental tyres were in second place, and the Gislaveds were right behind them. This was the second small, but real sensation. They let me handle the car with ease on the winding track. I had another surprise when the Goodyear UltraGrip Ice Arctic tyres were mounted on the Audi 3. The car braked and accelerated fairly well, but cornered badly. I even flew off the ice track in the first few laps. It s a good thing there were safety strips with a ten-centimeter layer of soft snow around me and not meter-high snow banks. But there were snow banks around the snow handling track Braking distance on ice (using ABS) 25 5 km/h, m 14 C Continental ContilceContact 10.4 Acceleration time on ice (antiskid system switched on) 5 25 km/h, s 14 C Continental ContilceContact 4.0 Ice track lap time, s 17 C Nokian Hakkapeliitta Winding track lap time on ice, s 17 C Nokian Hakkapeliitta Nokian Hakkapeliitta Nokian Hakkapeliitta Continental ContilceContact 26.6 Continental ContilceContact 79.3 Pirelli Winter Ice Zero 10.9 Pirelli Winter Ice Zero 4.3 Gislaved Nord Frost Gislaved Nord Frost Goodyear UltraGrip Ice Arctic 11.4 Dunlop Ice Touch 4.4 Pirelli Winter Ice Zero 27.4 Pirelli Winter Ice Zero 82.1 Gislaved Nord Frost Goodyear UltraGrip Ice Arctic 4.7 Michelin X-lce North Michelin X-lce North Dunlop Ice Touch 12.1 Michelin X-lce North Hankook Winter I'Pike 28.8 Кама Euro Michelin X-lce North Кама Euro Кама Euro Hankook Winter I*Pike 86.2 Bridgestone Ice Cruiser Gislaved Nord Frost Bridgestone Ice Cruiser Dunlop Ice Touch 87.3 Hankook Winter l*pike 12.9 Hankook Winter I*Pike 5.1 Dunlop Ice Touch 29.5 Bridgestone Ice Cruiser Кама Euro Bridgestone Ice Cruiser Goodyear UltraGrip Ice Arctic 29.8 Goodyear UltraGrip Ice Arctic 88.3 Gislaved Nord Frost Grip and handling on ice Grip on snow Grip on asphalt Pirelli Winter Ice Zero + Grip on ice Grip on dry and wet asphalt Average handling characteristics on snow Average handling characteristics on ice and snow Noise Overall score 8.8 Overall score 8.7

8 Skill, not numbers! There are only 96 studs with standard protrusion in the tread of Gislaved Nord Frost 100, but these tyres are better on ice than a lot of others with 130 studs. It was third best on the handling track, but was less than a second behind the leader, which had nearly twice as many studs German tyre makers (today Gislaved is a 100% product of Continental) worked on the new tread and new Triangular studs for a good reason. There is only slight skidding and it s easily controlled. Its performance on snow is decent, although abrupt breaks into skids interfered on the handling track. It has the shortest braking distance on wet asphalt. These tyres aren t too noisy, and they swallow bumps softly. They re well-balanced winter tyres overall. They re confident on the highway and are nearly ideally suited for city driving. The price is reasonable too. 38 standard sizes are available, from 155/70 R13 to 245/40 R18) 94 (670 kg) Weight, kg 8.8 Tread pattern depth, mm 9.4 Shore tread rubber hardness, un. 48 Number of studs/stud lines 96/14 Stud protrusion, mm Country of manufacture Germany We tested these tyres one and a half months before their official premiere (AR No. 17, 2013), and we didn t even know the model s actual name, because there was no marking on the smooth sidewall. However, the tread and new stud design were already commercial, and now both the stud insert and casing have a complex trapezoidal shape. The Pirelli tyres were almost equal to the test leaders in longitudinal dynamics. We noted abrupt breaks into side skids on the handling track. But Pirelli tyres, whether winter or summer, have always given a car sharper, more sporty reactions. Their behavior was similar on snow, but longitudinal grip was average. They decelerate well on dry and wet asphalt. Ride comfort is good, but there s a lot of noise. You can hear the roar even on packed snow. We also recommend these tyres, with a few reservations, especially for those who drive mainly on ploughed roads in winter. 29 standard sizes are available, from 205/755 R16 to 295/35 R21) 94 (670 kg) Weight, kg 9.1 Tread pattern depth, mm 9.5 Shore tread rubber hardness, un. 50 Number of studs/stud lines 130/16 Stud protrusion, mm Country of manufacture Germany Subjective rating of steering reliability on ice, points* Nokian Hakkapeliitta 8 10 Braking distance on snow (using ABS) 50 5 km/h, m 7 C Dunlop Ice Touch 25.9 Acceleration time on snow (anti-skid system switched on) 5 50 km/h, s 7 C Nokian Hakkapeliitta Winding track lap time on snow, s 8 C Nokian Hakkapeliitta Continental ContilceContact 10 Continental ContilceContact 26.0 Gislaved Nord Frost Continental ContilceContact 91.9 Gislaved Nord Frost Goodyear UltraGrip Ice Arctic 26.1 Continental ContilceContact 9.2 Pirelli Winter Ice Zero 93.2 Pirelli Winter Ice Zero 9 Nokian Hakkapeliitta Pirelli Winter Ice Zero 9.5 Goodyear UltraGrip Ice Arctic 93.4 Michelin X-lce North 2 9 Michelin X-lce North Michelin X-lce North Gislaved Nord Frost Hankook Winter l*pike 9 Gislaved Nord Frost Hankook Winter l*pike 9.7 Michelin X-lce North Dunlop Ice Touch 8 Кама Euro Кама Euro Dunlop Ice Touch 95.7 Bridgestone Ice Cruiser Pirelli Winter Ice Zero 27.3 Dunlop Ice Touch 10.0 Hankook Winter I*Pike 96.0 Кама Euro Hankook Winter l*pike 27.5 Bridgestone Ice Cruiser Bridgestone Ice Cruiser Goodyear UltraGrip Ice Arctic 7 Bridgestone Ice Cruiser Goodyear UltraGrip Ice Arctic 10.5 Кама Euro *On a ten-point scale. A higher value corresponds to a better result.

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11 Snow Photos: 1. The snow handling track is for slow hairpins and running turns, where the Audi 3 is accelerated to 100 km/h. The next day the temperature rose from 14 to 7 C. We had a 600-meter track with perfectly packed snow at our disposal. The job was monotonous: accelerate to 50 km/h, brake, accelerate again, brake again But unlike the earlier test, where the driver had to do some fancy footwork with the pedals to prevent the wheels from spinning too much at the start and locking during braking, now this was all done electronically with Traction Control and ABS. It seems like soon we won t need a driver at all. At the same time, a robot car was honing its skills on the next track! There was a driver at the wheel, but only to set the required driving modes and check that the robot was performing them properly. The electronic systems actuators stepped on the gas and brakes, and even turned the wheel. At the end of the track, the car turned around by itself and continued to take measurements in the opposite direction. I felt a slight touch of professional envy, but quickly cheered up, because this chunk of metal won t replace me on the handling track any time soon. By the way, they let me take a spin as a passenger in a car with a robot at the wheel, and Would this wise guy replace an arm or leg, to echo the English Luddites? Soon there won t be any need for tests on handling tracks either! This driverless car already knows how to do a moose test on snow. The angular velocity centers detect skids, and a command is given to correct it with the steering wheel. Another five years or so and these cars will be racing on winding tracks to compare tyres. For now, if we look as the results of manual tests on snow, we can see they re very close for braking. The difference between the best (Dunlop Ice Touch) and worst (Bridgestone Ice Cruiser 7000) tyres is less than three meters or within ten percent. The difference for acceleration is a bit larger, about 20 percent, and the favorite tyre here is the Nokian Nokian Hakkapeliitta 8. So the Finns not only fiddled with the studs, but also with the tread, since studs are less important in snow than the tread. The Nokian tyres were the most confident on the handling track, sweeping around the trees and snow-covered stones, with quick reactions and fully controlled skids. In fact, it was better not to apply the brakes in skids; otherwise the switched-off stability control system would activate and the speed would decrease. There was another feature too: I woke up the stability control system only once on the Nokian tyres, but it happened much more often on the others, because of errors caused by long-drawn-out skids (Bridgestone Ice Cruiser 7000 and Kama Euro-519 tyres were especially upset by them). Michelin X-lce North 2 + Comfort Grip on wet and dry asphalt Poor slush-planing resistance Low impact resistance Goodyear UltraGrip Ice Arctic + Braking properties on ice and snow Grip on wet and dry asphalt Impact resistance Handling on ice Traction on snow Overall score 8.45 Overall score 8.35 When we did this test in early February with Michelin X-lce North 2 tyres, we got an invitation to the official premiere of the nextgeneration X-lce North 3. But all of our attempts to wangle some of the new tyres for the test were a fiasco! Incidentally, not all sizes will be available in Russia, and the Х-Iсе North 2 will account for half the sales of Michelin studded tyres. They re decent tyres with the trademark features of Michelin tyres, like high stability on slippery roads and easy, straightforward transitions. Too bad the skids last a bit longer than we d like. This appeared on asphalt too: long-drawn-out skids interfered with moose tests at high speed. There were no problems with braking, though, and the comfort level was off the charts. They were the softest and quietest tyres in our test! The sidewall could be stronger, because the thin rubber ripped even at 40 km/h on hitting an obstacle. Most of the tyres held on to 50 km/h, and some even remained whole at higher speeds. Overall, they re very comfortable winter tyres that are best for level streets in large cities. Goodyear UltraGrip Iсе Arctic tyres introduced last year immediately became one of the leaders in our tests (AR No. 19, 2012), but their results less impressive this year. The reasons may have been different weather conditions or competitors progress, but the problem is likely lower quality studs. The triangle studs themselves hadn t changed, but most of them were sunk too deeply into the tread. Protrusion was an average of 0.9 mm, versus mm for competitors tyres. There had to be a reason for the lag behind the test leaders in acceleration and braking on ice. On the handling track the lag was already beyond decency. The Audi A3 on Goodyear tyres took ten seconds longer to travel the 800-meter track than the Nokians! Last year we noticed that Goodyear UltraGrip Ice Arctic tyres performed better in the longitudinal than in the lateral direction; and now the imbalance has worsened the car barely holds on in a curve! Handling is better on snow, but there are problems with acceleration. They re average on asphalt. It s interesting that the clatter of the studs is barely audible, but the tread whines at any speed. The one thing we all liked about these tyres was their impact resistance, where they came in third. With normal quality studs, these tyres could probably be a worthy competitor to the leaders; but based on our test results, we wouldn t recommend these tyres for cars without electronic stability control systems.

12 Tread pattern depth, mm 9.4 Tread pattern depth, mm standard sizes are available, from 175/70 R14 to 255/35 R19) 94 (670 kg) Weight, kg 9.3 Shore tread rubber hardness, un. 52 Number of studs/stud lines 118/12 Stud protrusion, mm 1.0 Country of manufacture Russia 25 standard sizes are available, from 175/70 R13 to 225/55 R17) 94 (670 kg) Weight, kg 10.3 Shore tread rubber hardness, un. 55 Number of studs/stud lines 130/14 Stud protrusion, mm Country of manufacture Poland Weight, kg 9.1 Subjective rating of steering reliability on snow, points* Speed at start of slush-planing (slush 35 mm deep), km/h Nokian Hakkapeliitta C Bridgestone Ice Cruiser Continental ContilceContact 9 Continental ContilceContact 21.0 Pirelli Winter Ice Zero 9 Pirelli Winter Ice Zero 21.0 Goodyear UltraGrip Ice Arctic 9 Gislaved Nord Frost Michelin X-lce North 2 9 Goodyear UltraGrip Ice Arctic 20.8 Gislaved Nord Frost Nokian Hakkapeliitta Dunlop Ice Touch 8 Dunlop Ice Touch 20.4 Hankook Winter l*pike 8 Кама Euro Bridgestone Ice Cruiser Michelin X-lce North Кама Euro Hankook Winter l*pike 19.4 *On a ten-point scale. A higher value corresponds to a better result.

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15 Asphalt Photos: 1. Gislaved Nord Frost 100 tyres has the shortest braking distance on wet asphalt. 2. Nokian Tyres summer test track has a specially certified section for testing pavement wear. A car on qualified studded tyres makes 200 passes on one side of a granite slab with a strictly defined size and then 200 passes on the other side. After weighing the studs before and after the tests, a committee makes a decision on whether to allow production in Northern European countries. It s possible this certification will be done in Russia too, since new technical regulations for winter tyres are now being prepared In early spring, we added and asphalt test cycle to our other tests. First, we looked at how the tyres performed in an even layer of slush on asphalt. The layer was only 3.5 cm thick, but the Hankook tyres started floating at only 19.4 km/h. The Bridgestone tyres were only a bit better, with a limit of 21.2 km/h. On wet asphalt without any snow cover, the Gislaved tyres had the shortest braking distance, while Nokian Hakkapeliitta 8 tyres were the worst. Yeah, I know, skeptics from other tyre companies have already whispered that the Nokians would perform badly on asphalt with that many studs. It s true on wet asphalt, but on dry asphalt the Nokian Hakkapeliitta 8 showed some of the best braking results. It s worth recalling that modern studded tyre perform as well or even better than Scandinavian-type studless tyres, popularly known as velcros. This is due to the stiffer rubber needed to hold the studs in place. The myth that studded tyres roll on asphalt more on the studs than the rubber is still making the rounds. In fact, when studs come in contact with asphalt, they sink into the tread, with hardly any decrease in the size of the contact patch. However, it all depends on the manufacturer s objectives are in designing a specific tyre model By changing the tread pattern and the hardness and chemical composition of the rubber, you can shift the balance of qualities, giving preference to either performance on slippery winter roads (ice, snow) or on asphalt. In the Dunlop Ice Touch tyres, this balance is clearly shifted toward asphalt. The Audi A3 braked confidently and responded best of all to sudden turns of the wheel. On ContilceContact tyres, the braking distance on dry and wet asphalt was a couple of meters more, so preference was given to winter qualities. Where studded tyres always lose out to studless ones in noise comfort. They always make more noise especially if there are 190 studs in the tread, like in the Nokians. However, even with fewer studs, the Kama Euro, Pirelli, Continental and Bridgestone are almost as noisy. The Michelin X-lce 2 is the quietest tyre, and along with the Nokian Hakkapeliitta 8, also the softest. How do these soft tyres behave if they hit a pothole or bump in the asphalt? We crash-tested summer tyres two years ago (AR No. 6, 2012). Now for the first time we did the same experiment on winter tyres. The car hit a piece of a U-channel steel bar placed at an angle of 30 degrees at 40 km/h. If the tyre survived, the test was repeated at 45 km/h, and so on until the tyre s last gasp. We didn t torture the suspension of the new Audi A3; we found a beat up Mercedes-Benz C180 instead. The Bridgestones survived the most shocks: we managed to punch them only a 70 km/h! That s no coincidence. The Japanese design their tyres for bad roads, strengthen the construction and carry out their own crash tests. The Continentals also stood up well to shocks they gave up at 60 km/h. Most of the tyres were finished off at 50 km/h, but the Michelins, which we liked so much for their softness, were punched in the first lap at 40 km/h. We even decided to repeat the experiment, because maybe it was just a fluke. Bang! Pss-ss-ss And the second Michelin X-lce North 2 was punctured and went off to the dump. Once again there was an explanation. Michelin is concentrating more and more on lowering rolling resistance by making the sidewall thinner (this reduces so-called hysteresis losses, i.e., the energy expended on heating due to deformation). We also tested the tyres for rolling resistance using a chassis dynamometer. As it turned out, the Nokian Hakkapeliitta 8, and not the Michelin X-lce North 2, rolled easiest of all. But this was without studs, since studded tyres would have damaged the calibrated surface of the dynamometer. It s not certain that this rating would change with studs. But in terms of fuel consumption, the difference was still small, since most of the tyres were separated by l/100 km. The difference between the most economical and the greediest tyre (the Bridgestone, as expected) was 0.6 l/100 km. Even so, since we performed the experiment without studs, we didn t count the results in the final ratings. Look, think and choose. If you ve decided to stay with studless winter tyres, wait for the next issue of Avto Revu. We tested 11 more studless tyre models. Using pliers and some choice idiomatic expressions, Uncle Vanya rated the pull strength of the studs, while a dynamometer held the tyre and displayed the boring figures. Photos: 1. Thanks to well-organized work space in the garage, changing tyres took no more than five minutes. 2. We used two methods to rate noise comfort: we recorded noise pressure with a Brüel & Kjær professional sound level meter and rated tyre noise subjectively by listening. Braking distance on wet asphalt from 80 km/h (using ABS), m +7 C Braking distance on dry asphalt from 80 km/h (using ABS), m +9 C

16 Gislaved Nord Frost Pirelli Winter Ice Zero 35.7 Michelin X-lce North Dunlop Ice Touch 36.1 Bridgestone Ice Cruiser Goodyear UltraGrip Ice Arctic 36.6 Continental ContilceContact 37.9 Кама Euro Hankook Winter l*pike 38.6 Nokian Hakkapeliitta Dunlop Ice Touch 33.5 Gislaved Nord Frost Nokian Hakkapeliitta Goodyear UltraGrip Ice Arctic 34.0 Pirelli Winter Ice Zero 34.7 Michelin X-lce North Hankook Winter l*pike 34.9 Кама Euro Continental ContilceContact 35.4 Bridgestone Ice Cruiser Dunlop Ice Touch Bridgestone Ice Cruiser Grip and handling on asphalt Braking properties on snow Handling on ice and snow Ride comfort + High impact resistance High slush-planing resistance Grip and handling on asphalt Grip on ice and snow Handling on ice and snow Comfort Overall score 8.25 Overall score 7.45 In the final rating, the Dunlop tyres were only 0.1 points behind the Goodyears. That s not surprising, since Dunlop is now 75% owned by Goodyear, and Dunlop Ice Touch and Goodyear UltraGrip Ice Arctic tyres were designed by the same team of engineers (AR No. 4, 2012) They have different tread patterns, but everything else, like tread depth, rubber hardness and studs, are the same. Unfortunately, the stud quality is also identical. The studs on the Dunlops were also set deeper than necessary. Incidentally, the studs are made at the same plant in Poland. They have similar handling problems on ice as well. The Dunlop tyres hold noticeably worse laterally than longitudinally. Driving the car on the winding track was difficult because of abrupt, unexpected breaking into skids. But it has the shortest braking distance on snow! At the same time, acceleration and handling characteristics are as sluggish as on ice. Then on dry asphalt, it has the shortest braking distance and the highest moose test speed. The car responded quickly and precisely to turns of the wheel, which is rare for winter tyres. Of course, there s the side effect of increased stiffness on small bumps. Like the Goodyear tyres, we recommend the Dunlops for those who usually drive on ploughed roads in winter. Aggressive, jagged with fine, wave-like sipes and 14 lines of studs. But they re regular studs with cylindrical inserts, and the tread rubber isn t as adhesive as in the competitors, as shown indirectly by its increased hardness: it s 20% more than the Nokians. The result is very modest grip on ice and snow. Handling could also be better (speed in turns is limited by unpleasant front axle skidding). But then on slush, the Bridgestone tyres started floating later than the others. They also perform superbly on asphalt. Reactions in moose tests are fast and precise, as if the car was shod with allseason instead of winter tyres. We liked the impenetrable sidewalls most of all. But there s a compromise here, since stronger sidewalls are also stiffer, so the Bridgestones didn t give the most comfortable ride. Bridgestone Ice Cruiser 7000 will probably find its less affluent buyers, especially out in the sticks, where tyres get changed often, not because of tread wear, but because of flats caused by hitting potholes. By this fall, dealers will already be offering the new Blizzak Spike- 01 model as an alternative to the Ice Cruiser 7000 (see the upcoming issues of AvtoRevu for details), but we won t be able to rate the improvement in comparison tests until next year. 16 standard sizes are available, from 175/65 R14 to 225/55 R17) 94 (670 kg) Weight, kg 10.1 Tread pattern depth, mm 9.8 Shore tread rubber hardness, un. 55 Number of studs/stud lines 130/14 Stud protrusion, mm 0.9 Country of manufacture Poland 37 standard sizes are available, from 175/70 R13 to 245/50 R20) 91 (615 kg) Weight, kg 10.6 Tread pattern depth, mm 9.7 Shore tread rubber hardness, un. 59 Number of studs/stud lines 130/14 Stud protrusion, mm 1.0 Country of manufacture Japan Hankook Winter i*pike + Price Grip and handling on dry asphalt Grip on ice and snow Low slush-planing resistance Grip on wet asphalt Kama Euro Price Braking properties on snow Grip on ice Handling on ice and snow Low comfort level Overall score 7.45 Overall score 7.1

17 Even at the static measurement stage, we assumed that the Hankook tyres were irrelevant in this test, since most of the studs barely protrude from the tread. There are some that stick out only 0.3 mm! Of course, these studs didn t work on ice, and the car skidded dangerously during braking and in turns. But they still got a decent rating for steering reliability. Yes, the car skidded and that s why it moved slowly, but the grip limit felt good, the breakouts were smooth, and the successful balance of drift and skidding was obvious. It happens. Of course, the Hankook couldn t show off on snow either, where the studs were no longer important. The tread didn t drain very well, and started floating before the others on slush. They also performed badly on wet asphalt (braking distance was too great), were sort of OK only on dry asphalt. That s not much of a recommendation for the Hankook Winter i*pike as a winter tyre. On the other hand, there s an argument that s louder than reasons of safety: Hankook tyres are exactly half the price of the Nokians. 64 standard sizes are available, from 155/55 R13 to 215/55 R18) 91 (615 kg) Weight, kg 10.0 Tread pattern depth, mm 9.4 Shore tread rubber hardness, un. 57 Number of studs/stud lines 130/12 Stud protrusion, mm Country of manufacture South Korea Despite a tread pattern very similar to the Nokian Hakkapellitta 4, Russian-made Kama Euro-519 tyres still can t compete on equal terms with their imported counterparts. Longitudinal grip on snow was encouraging, but all hopes vanished on the handling track. It was hard to prime the car for turns, and before each of them we had to reduce speed more than for the others. It s the same sad story on ice: skidding is really unpredictable and hard to control. There are problems with braking on ice as well.. The reason is similar to the problem with the Hankooks: the studs don t protrude far enough above the tread surface. The average is only 0.8 mm, which isn t much for good grip on ice. Their performance on asphalt is middling. Responses to the wheel are smeared during sharp maneuvers. Even though the tyres don t clatter that much, the tread hums a lot. And these tyres were one of the stiffest on bumps. The Kama Euro-519 came in last in our test. But if you recall the price and the stellar cast of participants, it s not only last place but last place of honor. If the manufacturer sets up quality control of the studs, maybe they ll be able to claim a higher place of honor, rather than the lowest. 16 standard sizes are available, from 175/70 R13 to 215/60 R16) 91 (615 kg) Weight, kg 10.3 Tread pattern depth, mm 9.0 Shore tread rubber hardness, un. 59 Number of studs/stud lines 136/14 Stud protrusion, mm Country of manufacture Russia Rated fuel consumption according to bench measurements of rolling resistance coefficients, l/100 km Nokian Hakkapeliitta Goodyear UltraGrip Ice Arctic 6.0 Dunlop Ice Touch 6.2 Gislaved Nord Frost Hankook Winter l*pike 6.2 Michelin X-lce North Pirelli Winter Ice Zero 6.3 Кама Euro Continental ContilceContact 6.3 Bridgestone Ice Cruiser Stud pull strength, N Continental ContilceContact 232 Bridgestone Ice Cruiser Кама Euro Michelin X-lce North 2 90 Gislaved Nord Frost Dunlop Ice Touch 86 Goodyear UltraGrip Ice Arctic 84 Pirelli Winter Ice Zero 84 Hankook Winter l*pike 74 Nokian Hakkapeliitta 8 48 Approximate retail prices in online stores for tyres, rub. Кама Euro Hankook Winter l*pike 3600 Bridgestone Ice Cruiser Dunlop Ice Touch 4400 Gislaved Nord Frost Goodyear UltraGrip Ice Arctic 4900 Pirelli Winter Ice Zero 5100 Continental ContilceContact 5300 Michelin X-lce North Nokian Hakkapeliitta