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[Sun Hat]

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[KCM5]

Do you already have a bike? If so, I'd stick some studded tires on that bad boy and get going. The studs are great for ice/packed snow but don't do very well in deep snow (more than two or three inches) or slush. I think it's not that they don't do well, actually, more that they don't give you any advantage over non studded tires.

Are the sidewalks shoveled or do they get really rutted? Ruts are really hard to deal with and I'm not sure what that answer to those is - probably a fat bike, but I've never had one so I can't give you any advice on that.

I ride in a cold/not too wet place and find that the studs are really important for me as we get quite a bit of glare ice/packed snow on the side streets that I ride on. If I were riding on main roads that are salted I wouldn't need the studs and would just ride on mountain bike tires.

[kelvin]

Start with what's cheapest and easiest. When it doesn't work right, when you've killed it because you're overusing it and the cheap solution can't handle the strain, that's when you upgrade and spend real money. 

I highly recommend disk brakes for winter riding.

Good luck!

[GuitarStv]

The conditions you ride in will determine the answers you need.  I've been commuting 22 km each way in Toronto's winters (some snow that's usually less than a foot at a time, lots of salt, pretty quick road clearing, not much ice) for five years and generally use 28x700C touring tires with a little bit of a knobby pattern on them.  I stay exclusively on the roads in the winter . . . sidewalks and bike paths aren't plowed.  Narrower tires punch through snow and slush to give you traction on the road.  Touring tires are heavier, but have decent flat protection (changing a flat in the winter is horrifically terrible).  I'd rather have disk brakes, but have been able to make due just fine with rim brakes (be aware - stopping distances will be increased, but not to an unsafe level) with Kool-Stop salmon pads.

I agree with previous posters - try it with what you've got for a few weeks.  Figure out what needs to change, and slowly modify things over time until you're happy.  4 km is short enough that in a worst case scenario you can always hoof it back home if things feel unsafe or a problem occurs.

Note - clean the salt off your components regularly if you want them to last.

[frompa]

I ride throughout the Winter, in sometimes snow and ice, the sort that hangs around on the side roads for weeks, freeze at night, thaw a bit during the day.  Based on that experience, I recommend a studded front tire, for the traction you'll need.  You can find on-line instructions for making your own -- you basically punch wood screws through a tire, be sure to line the tire before you put in the tube, and you're good to go.  I have also used commercially produced studded tires, and found no difference, except that the home-mader was WAY cheaper. Best of luck!

[infogoon]

When I was bike commuting in the snow, my rig of choice was a ~$200 fixed-gear road bike with studded tires. The fixed gearing made it really, really easy to feel when the back end started losing traction and adjust accordingly. Also, no gears means no slush and salt to clean out of the derailleur.

A friend of mine has a (similarly cheap) fatbike from Mongoose or some other department store brand that he swears by for winter riding.