Can a fatbike cross frozen car tire ruts without slipping?

Question

I'm investigating winter commuting options (it's never too early to start thinking about next winter...). I'd love to keep biking in the winter, but I've had some scary experiences falling on ice, even when riding a mountain bike with studded tires. I wasn't hurt when I fell, but I don't like falling and I don't like being scared (especially now as I'm hitting my mid-forties!).

I'm curious whether a fatbike would give me a stable enough experience to keep me riding in the winter, but I don't know anybody who has one that I could borrow for testing purposes. So I was wondering if folks here might have experiences they could share?

The particular condition I'm concerned about is the ice that forms when there's slushy snow on a poorly cleared road which then freezes hard, preserving the shapes of the intersecting tire tracks left by cars. Inevitably I'm going to end up hitting them with my bike. On a fatbike, would I be able to stay upright?

Answer 1

I don't have a fat bike, but I do have experience with Norwegian winter.

Frozen tyre ruts... That's about the worst you can put a bike in. A fat bike with studs might fare slightly better than other bikes, but I wouldn't trust anything short of a 4x4 or tracked vehicle in such a situation!

The only safe thing to do there is to drop the saddle, stay seated on it, extend one or both legs so you can balance better as well as dab the ground if necessary, keep a slow but steady pace, and avoid crossing ruts at acute angles. With enough practice, this should ensure you survive even the worst ice nightmares, but it will never be exactly safe, or fun, on any bike. A fat bike will mostly make it easier to keep the pace in the presence of loose or slighly slushy snow. But as soon as you're on hard ice or slush-on-ice, only the length of studs has any influence on grip. Having long screws protruding from the tyres would probably help more, but then the bike would hardly be able to roll on tarmac anymore.

The most important preparation really is to look ahead, recognize the danger, adapt your riding suitably, and know when it's better to get off entirely. (Which may not even help with normal shoes: I sometimes put on my Snowline Chainsen as studs for my feet when riding in icy conditions. Without them, it can feel safer on the bike than off it.)

Again, what the fat bike does offer is to make it much more feasible to ride on snow. That means you may be able to avoid the icy parts more often, and it can also simply make it more enjoyable to ride the bike at all when the conditions are such. I personally enjoy winter riding on normal MTB tyres with studs, which have the advantage of not quite as extreme rolling resistance on tarmac, and on packed snow they actually work very well (drop the pressure, 1.5 bar down to only as low as 1 bar), but on loose snow it's just silly and impractical for any distance of more than a couple of meters. I think that is still tough on a fat bike, but perhaps doable.

Answer 2

My experience of riding in winter is that ice isn't the problem if you have studded tires. Snow is.

I have never ridden a regular 622-40 stud-tired bike in icy conditions where riding would be dangerous (so presumably studded tires on a fatbike will work perfectly in all ice conditions too). However, when stopping at traffic lights, when you have to put a foot down, that's where the danger starts and you have to be careful not to crash when stopped. The tires I used were Nokian / Suomi Tyres (former name / current name) W240. Perhaps some tires with studs only in the middle might be dangerous in some icy conditions; W240 has four lines of studs and when using it, I never encountered any dangerous icy condition.

However, snow is a problem. A very big problem.

Firstly, you notice that fresh snowfall can be ridden through, but once pedestrians have made the snow layer uneven before it has been plowed, riding is very annoying. A fatbike might make it less annoying since you can reasonably run reduced pressures.

Also when roads aren't plowed often enough, they might develop a thick layer of hard snow. When the spring arrives, and snow melts, that thick layer of hard snow becomes a thick layer of soft slush-like snow. Riding through that is practically impossible and very dangerous. So even if roads are 99% free from snow, the remaining 1% slush-like snow can be a genuine hazard and you might want to dismount and walk. If roads are plowed often enough, this problem doesn't happen, but then again you can't rely on all roads being plowed often enough -- even one minor part of road where plowing was skipped during a snowstorm can eventually become a genuine hazard during the following spring.

Fatbike with studded tires solves all ice problems and many snow problems but not all of the snow problems. There are still environments that have snow and can't be ridden through with a fatbike.

The voice in this video is Finnish but this video even for non-Finnish speakers demonstrates that fatbike doesn't solve all snow problems (and that it's a bad idea to use non-studded tires on fatbikes during winter):

I'm sorry but a bike is not a car. If public transportation is not an option, in areas that have winter car is mandatory (or you could use a taxi during the worst days...). You might want to ride bike often though instead of a car, even during winter; in many winter weathers including snowstorms, fatbikes work well. But there are road conditions where a bike just won't work. Especially if bike paths are segregated and plowed less often. Well-plowed paths are safe.

Answer 3

From experience, studs contacting the road reliably at any position of the wheel keep the bicycle well enough on the track under these conditions. Under concentrated, focused steering, the risk of falling down is not excessive. However frozen ruts have very uneven surface that is incredibly tiresome and difficult to ride. It is also slow in comparison to any more normal road.

Answer 4

If you ride in really demanding ice conditions (e.g. smooth wet ice or frozen tire ruts), you will need good studded tires. I don't have a fatbike, but I run Schwalbe Ice Spiker Pros on my MTB. These or similar high quality studded tires should get you safely across basically any kind of ice.

Answer 5

Slick ice is easily navigated by bike, but refrozen slush is tricky to maneuver. The best strategy (after experience over only two winter riding seasons, so take that with a grain of salt) is to accelerate.

Maintaining a faster speed means that when you do hit a 3-4 cm peak, the momentum will be enough to jump over.

If the height difference runs along the track of the bike rather than perpendicular to it, what matters most is to make sure the tyre doesn't suddenly shift from one path to another. "Falling down" to another track knocks the bike from under your weight, and you need to be attentive to recover in time. In the summer speeding with a road bike over a fallen tree cone has a similar effect.

Incidentally, a fatbike is not particularly necessary on snow/slush/ice unless you want to ride on fresh snow (or on sand in the summer). But being the first cyclist on fresh snow is tough. In my experience just 250 meters on one foot of fresh snow are exhausting, and if the speed drops so much that the bike stalls, you have to be ready. Your mileage may vary, literally. The good news is that falling while clipped-in in a foot of snow is not too bad, because of the cushioning of the snow. See also: What is the smallest collection of bikes to maintain for these three types of snowed over paths?