Yep, glare ice is exactly what studded tires excel at. They're less effective in rutted ice, and even more so on ice covered by a layer of powdery snow.

I'll take the temperature into consideration when deciding to use the studs or not. If its above freezing and they're not calling for much I am more likely to leave the road tires on. If its below freezing and/or they're calling for a considerable amount then I use the studs. But anytime they call for anything over a inch and its around 32f/0c then I'll put the studs on. I learned a long time ago not to take any chances. There have been lots of times when I could've probably gotten away with using the road tires. But I don't want to risk it. Sure, it might take an extra 5 minutes or so. But I'd rather be safe than sorry. I use Nokian Gazza Extreme 296's. There is nothing that they can't handle. They take on solid ice like its nothing. I've ridden in empty parking lots that had glare ice on them. And did a bunch of big 'S' turns and didn't slip once. They are starting their ninth winter. I can comfortably ride in 8" of snow. Above that I just improvise. The key to riding in deep snow is to keep spinning and moving forward. It may take longer but at least I'm moving. Practicing riding a straight line comes in handy for riding down a tire track when the need arises.
I have them mounted to a spare wheelset that matches my road rims. I use Rhyno Lites. It takes me less than 10 minutes to switch wheels. Lots of times I've made that last minute decision before heading out to switch wheels. Once you get past the cold, winter riding is like nothing else. I look forward to the challenges that Mother Nature throws at me. The weather around here isn't too bad. Nothing that I can't handle. I'm 59 and I know my riding days are winding down so I do it while I can. Besides its good for you.

If in doubt, put em' on.

I don't ride on roads during winter. I've seen too many cars sliding out of control and don't want to be in their way. Not to mention my dislike of getting sprayed by the wake of passing cars and trucks. That doesn't end my riding though. We have a pretty good and growing network of protected bikeways so I can still ride to a number of places for eat and drink, groceries, pharmacy, hardware, bank, etc.

If I'm in doubt I'll use a bike with studs (Schwalbe Marathon Winters on a Workcycles Omafiets). They do a good job of keeping the bikeways clear so most days I can ride a bike with regular tires. I'll also keep the studded tires high pressure if there's doubt and that way I can let a bit out if I need more bite.

Yeah, when I got studded tires and got them for my dad to, we went out riding and to demonstrate how well they gripped ice I rode right onto an ice skating rink with them. The bike and the tires grip great - though (lol) if you try to put a foot down you'll quickly find out your shoes lack studs.

With good studded tires (like w106's that the other poster has, or Schwlable Marathon Winters like I have), I always aim for glare ice rather than going for a snow/ice mix. Snow can be slippery and slip around on the ice, glare ice is rock solid traction.

Thanks, I will try that.

Fyi, other posters mentioned this, but many studded tires are designed in such a way that inflating them to high pressure brings half or all of the studs off the ground. Schwalbe Marathon Winters have 4 rows of studs, at high pressure only the 2 center rows hit the ground. When you want more traction on ice let some air out of the tire and you get 4 rows of studs in contact with the ground. 45nrth Xerces tires have 2 rows of studs, at low pressure they don't contact the ground when going straight at all. The idea being that if you start slipping the tire starts to slide and catches the studs. Or you can let air out, and have both rows in contact with the ground if the weather changes while riding or on your way home.

Once I start seeing any ice on the road I always ride the bike with studded tires for the rest of the season. But, I do ride them at high pressure when the conditions are better, they're faster rolling that way.

Here in Minnesota I haven't seen any storms yet, last night I was riding my road bike with no studs - it's kinda funny, it's still noticeably slower when it's around freezing than it is when it's warm out. Something about the colder air being denser, grease in the hub getting the same way, and the rubber on the tires being less pliable or something.

A particularly good reason to wear a rearview mirror.

On my most memorable snow day, I accidentally knocked my mirror off, and spent about 45 minutes fruitlessly looking for it. When I got to work, I was chided for coming in later than usual, because they were worried about my riding in that weather. Normally I would be the first one in on that kind of day. I particularly remember riding up a hill the cars could not climb.

Good tip, but in my experience, I have not found that necessary. I prefer the reduced rolling resistance of my Marathon Winters at higher pressure, about 65 psi, but I take riding on ice carefully. A good description I have read is that the traction of studded tires is like walking on sanded ice.

Or you do what I do and make sure your city builds good protected bikeways and stay on them. No worries. No need for a mirror. No need to check a mirror or worry about a car sliding in to you or spraying you with slush. No getting honked at or yelled at by irritated or immature drivers.

I'm not sure how much good a mirror would do anyway. A car going 30 or 40 mph coming up on you suddenly looses it when they begin to move over to go around you. You really think you have time to react?

Exactly. The last time I snapped my fingers three protected bike lanes popped up in three different townships along my commute. Shazzam!

Mind paying us a visit? We'll take up a collection for your flight. Is there a limit to how many you can produce in a day? :-)

You might disagree with me, but I do not agree. I find it to be the opposite of what people would assume - sheer ice is great like 80% the traction of dry grippy pavement (with studs). Packed snow is fine to.

What I treat like walking on sanded ice is a thin layer of snow on top of ice, slushy half frozen snow, or deep snow. Those have all caused me problems - whereas sheer ice is just fine. I mean I'm definitely not doing crazy mountain bike tricks on sheer ice, just riding across it, but I don't find sheer ice takes to many precautionary measure. Tire studs are really effective at gripping into it.

I have no disagreement, especially about winter cycling with a Minnesotan, but I expressed my personal preference. (Among my group of capable, professional consultants at work, I might politely say, "I can't disagree with you, but I think you're wrong." )

Is sheer ice the same as black ice? Even at 80% of the traction of pavement, I still ride carefully on it. Even with seemingly just snow on the ground, I can't always be sure if there is ice below.

I had the right bike this morning. The road looked wet after some snow had fallen last night and then melted. There were slick patches. I could see the road glisten under the street lights. I took the CX with the Schwalbe winters. It made all the difference in the world. There was no drama. I cornered slowly. Overall speed was a few km slower, but didn't matter. Got here safely and on time.

Mission accomplished.

Lol...

Like I said, I'm more afraid of snow on top of ice than I am on sheer/black/uncovered by the blemish of thy wintery snow / ice. As they say in HR perhaps we'll have to agree to disagree.

I compare riding with studs on ice to riding on gravel. It's sufficient enough traction to be safe as long as you're not getting crazy around the corners.

Lowered PSI to 35, went riding in the snow. Encountered streetwide swaths of ice and felt secure! I will eventually up my speed. Thank you again for the suggestion!

haha yup, I can relate. that's what decided it for me to buy them. I swore I wouldn't, but it didn't take more than a few minutes on black ice to scare the cr*p out of me

My good man, I just carry a set of my spiked tires crossed in my back, like the old racers did.