Hello

Go for spikes, 4-5mm.
Rubber on snow/ice = no grip, very dangerous
Spikes on tarmac = some grip, like street tyres on gravel
Spikes on snow/ice = fun, fun, fun
https://www.youtube.com/watch?v=kPFVJctkhvk

At first I used manufactured tyres and on the rear I lost the middle part of the spike by going 100 kmh on the black road.
Now I go not faster than 60 kmh on the black road.
I would recomend to use self-screw spikes and a MX tyre (Mitas C02), so you can replace wornout spikes yourself.
Also when the tyre is done you can use the spikes that are still good for the next tyre.
The spikes of the manufactured tyres can't be reused, so on the long run more expensive.


The problem ist that the roads are not all white, often it has just a litte stripe of ice in the middle of the lane, and that is where the grip is. With the long spikes it's important to stay on the white roads or they get wornout very fast.
https://www.youtube.com/watch?v=8FN6Uf9PRak

If you stay off the main routes like E6 the roads are more likely white.
Sweden is better in the south than Norway along the coast.
Little snowfall and lots of traffic is bad for good white roads.
Coverd with snow, even the forrests with heavy lumber areas in Sweden are very nice to watch.
https://www.youtube.com/watch?v=kjBPFZTV2GE

I did two trips to southern Norway and Sweden up to Trondheim/Ostersund.
First trip was late dezember 2014 with short daylight, 0° to -28° at night, average -10° to -15° on the bike.
Second trip was in february 2016 with more daylight, +5 to -15° at night, with rain where it was supposed to be -30°.
Both trips were 2 weeks return from Switzerland so 4-5 days lost just to get there.
I stayed in hostels that I booked online just for the next days.
Wanted to go further up north but the affordable acommodation is getting to sparse.
I'm dreaming of doing it with a tent next time, but let me tell you:
"It is f*****g cold up there on the bike".
I was dressed in many layers and it worked on the bike when sitting still/riding, but I can't imagine to build up/down a camp like that without getting soaked in my perspiration. So the clothes get wet and will freeze at night in the tent.

Have fun
sushi

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