Given
83%
while driving a
Ford Focus mk2
(225/45 R18) on
a combination of roads
for 6
average miles
Coming from Finland, a country of winter snow and studs. Have these on two cars
- 2007 Focus Cabrio
- 1998 996 C2
In most winnter conditions amazing grip level. However, two shortcomings. 1) The modern light studs do not penetrate well if there is loose snow on top of hard snor/icy surface. Obviously this has more to do with regulations rather than the tyre brand and model. 2) These modern silica tyres seem to collect a layer of snow in slow speeds, say below 30..40 km/h . Both these properties make the tyres a bit Jekyll and Hyde. At best it gives enormous amount of grip but then you come on loose snow and you think you are driving very slow - and suddenly you have absolutely no grip. I wish we could still have the longer studs. I can tell it is not nice to get the impression of good grip for some 50 km (0.3 < muu < 0.5) and then in an open place wind has collected snow on the hard snow surface and a deer runs into your lights and you find absolutely no grip at all (like muu = 0.05). Fortunately I had my insurances. I dont think this would have happened with the old style big block, long heavy stud Hakkapeliittas. Those would have not given the level of grip on the 50 km stretch but they would have lost pretty much nothing coming to the loose snow.
What impresses me is the strong stud base. The cavity seems wrapped with a very strong compound and the studs seem to not come off at all. The construction of the tyre seems very good for winter purposes, not too stiff nor too soft side wall. Subjectively I think I would prefer a sharper shoulder but that is more like an image in my head rather than supported by my driving experience.
If I was to develop this tyre I would look into the slow speed attached snow layer phenomenom - perhaps on all the silica tyres. I also would like to try something like raised tread on the lines of studs to get the modern studs penetrate better the loose snow on top of the hard.
I know one problem with the winter tyre testing is that the tracks are always similar to get good comparability. But in real life the surfaces vary much more in winter conditions and a good winter tyre should even the grip levels to predictable. As good as the X-Ice 4 is it is not the most predictable tyre. Fortunately you can learn to predict the places where you will loose the grip. I find this all more of a result of rather compromized regulations than tyre makes development work.