I would liken riding in snow the to riding in mud. That is unless you hit ice underneath it. For mud riding I use a 1.8 Mud specific tyre. It is a Panaracer Mud Pro and it has several qualities I like. First of all it does not skate across the top- it bites through the Mud/snow and gets grip on the firm ground below. Secondly- it does not pick up the snow/mud and sheds it pretty quick-hence not building up around the forks and stays to act as a brake. and thirdly the tread pattern grips. I have used these in 6" of snow on a very cold morning with Ice underneath the snow and in ruts and they work.
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How long was I in the army? Five foot seven.
Spike Milligan