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Are winter tires needed in Denmark on a velomobile? It depends on how the winter is progressing. Cold but no ice and snow only slightly, it is not necessary with the spiked tires, then tires with the soft rubber and good pattern the better.
Spike tires is an advantage in icy and hard packed snow. In deep and loose snow a disadvantage
I chose something in between. Schwalbe Winter does not have as many spikes fit to drive on dry roads and in snow and ice. If I can not get ahead in the snow with them, it is better to stay home:-)