Gravel Cyclist's Tire Dilemma: Knobbies or Slicks? 6/8
Read this, if you are a critical thinking gravel or allroad cyclist
Cycling on Ice and in Snow
Riding slicks on ice is insane. I only tried it out of curiosity, and at extremely low speeds. As tires are the same cold as ice, there occurs no sticking traction between tires and ice. Thus cycling on ice with slicks is near to impossible. It requires excellent balancing skills and LOTS of patience. Even then, it can only be performed at very low tire pressures and extremely low speeds, without cornering, and with practically inevitable falls every now and then. Riding on ice with knobbies is often even worse due to squirm of knobbs.
Ice on the Hilba river wasn't rideable last winter.
I only dared to ride the most safe looking ice near banks of the Hilba river. Snow was a bit wet. It clung to tires (Suomi W240 A 40 mm), making the ride difficult.
On ice covered gravel roads, only studded tires were really an option to go for. But even on heavily studded winter tires (Suomi W240 A, 240 studs per tire), traction on ice was poorer than on ice-free gravel.
Studded winter tire on snow and ice covered gravel road. Suomi W240 A on the photo.
In certain conditions, too often encountered during Estonian winter, even studded tires struggled for their grip. The conditions I have in mind are these: gravel roads full of ice covered ruts evenly hidden by 2–4 centimeters thick snow.
That thick snow is too thick to allow tire studs to penetrate through it, yet at the same time, too shallow to behave as an independent snow surface. What happens is this: the studded tire presses agains the snow which slides, together with the tire, along the ice under the snow (the first chance of falling). Once the sliding starts, the tire will sooner or later diagonally hit an invisible ice-covered rut edge or their combination (the second chance of falling). The rut (system) will take your tire in. As you don't see where the rut is going nor how wide and deep it is, it is very hard to ride exactly in the rut (the third chance of falling). Even if you manage to ride exactly along the rut, there may be some other ruts crossing the rut you are riding it. Where frozen ruts cross each other, there are lots of unvisible and unflexible edges of irregular shapes under the snow (the fourth chance of falling). If you somehow survive this, you still can't climb out of the rute you are riding in (try it, and you'll risk the fifth chance of falling) due to steepness of its ice-covered edges and the slippery layer of snow between the rut and your tires.
To sum up, cycling in such conditions can turn into a nightmare, unless you take it as an extreme sport pushing your balance skills and patience to, or rather beyond, their limits.
Different snow and ice covers might look very similar to each other. Until you try them out, you can't really know how rideable they are. This particular one, for instance, looked like nothing special. It turned out that it had some nasty and poorly visible ice patches that were hidden by compressed snow. On these parts, the heavily studded tires felt like slicks, offering practically no traction at all.
In snow, slicks' traction is more or less the same as on ice, that is, non-existent. Big knobbed tires, on the other hand, worked well in snow. Snow-specific tread pattern with studs (Suomi W240 A) was the best option to go for in snow (please bare in mind that fat bike tires were not tested here!), because at temperatures below zero degrees Celsius some ice should always be expected. Cycling with studded knobbies on gravel roads covered in around 7–25 cm dry snow reminded me of cycling in dry sand. At the same time, it differed from sand in that it was slightly less sinking-in, a bit more slippery, a bit softer, and, for me personally, even more fun.
This field lane - frozen grass and frozen puddles under the snow - was bumpy to ride, but the studded tires offered an excellent grip.
To sum up, riding ice and snow covered gravel roads can be very challenging, in particular if the roads have ruts. Thus, heavily studded tires with deep winter specific profile are the best option, if very high rolling resistance and weight still feel better than broken bikes and bones.
THE END OF PART 6/8
Credibility of the Article
The author of the article is Matej Goršič [Matey Gorshich], 41, male, PhD, who has been an active sportive cyclist for 28 years. In his youth, he trained, and competed in, road cycling and athletics. Once finally out of the competitive waters, he started consciously re-defining his understanding and practice of cycling. Today, he feels most at home in a creative mixture of non-competitive, electronic-devices-free, self-exploring, adventurous allroad cycling. During last 3 years, he spent over 25.000 km mostly on tiny gravel roads of South Estonia.
The tires tested for the article were bought by its author at normal market prices from different cycling shops in Europe. There have been no sponsors or donations for writing the article nor for mentioning brands and items in the article and showing them in its photos.