My winters go up to -15 C. Roads are plowed and salted regularly. In those conditions: old 1996. rigid MTB with Schwalbe Marathon Winter tyres 47-559 works perfectly. I lube cables and shifter pivot points with fully synthetic engine oil and they don't freeze up. My ride is on flat land, so V-brakes work wonderfully even in the snow.
Your conditions may vary. Deeper, unplowed snow asks for fatter tyres with more deep thread. I'd recommend front tyre to be studded as well, at least the front one (for hilly rides, make it both).
For hilly terrain, I'd recommend disc brakes.
Also for -40C - some synthetic oil in a gear hub, instead of grease and no external shifters, since they would freeze. If flat terrain, then a fixed gear would be simpler, cheaper solution.
Originally Posted by
ThermionicScott
4 km = 2.5 miles. That's walking distance, as far as I'm concerned. No need to spend money on a bike if your goal is not to drive a car.
4 km is about 40 minutes of brisk walk and 10 minutes on bicycle. 20 vs 50 minutes in the snow.