Tires Wide tires with widely separated knobs work best on snow. Panaracer Dart 2.2 front and Continental Pro-2 rear are the best tires we've found for soft snow. Sometimes 5 psi feels great. Only glue one side. 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.