Snow Cat rims improve flotation, traction and stability on snow or ice. Studded tires improve traction on ice. Chains improve traction on snow or ice but dig themselves in on soft snow and give a rough, slow ride on pavement. The loads on bicycle bearings are so slight that just about any grease will protect them. We put low temperature grease in bicycle bearings to make them easier to pedal and steer.
Some bicycles have grease in their freewheels that can cause problems when it gets very cold.
We can disassemble the freewheel, clean it out, and put small amounts of low temperature grease in the right places. The grease we use is good year round, it doesn't have to be changed for summer. So repack bearings in the fall with low temperature grease and call it winterizing. The best we've found so far is Lubriplate Mag-1. This can help your bike shift better in winter.