Thursday, January 8, 2015

Defeat winter on your bike - cycling at subzero temperatures

First, a little explanation. By "subzero" I mean sub-American degrees zero, which translates to about -19C. Otherwise you would be thinking - where is the challenge in that?

Every single year in January we get a week or two when temperature drops to single digits Fahrenheit or below -15C. This morning my kitchen's thermometer showed -20C outside and it made me think twice whether I should attempt riding my bike to work. It takes me about 50 min. to ride 10 miles and it might be an unpleasant ride in such conditions. But when I checked on my car, it failed to start. No wonder, the battery was weak and I haven't used it in over a week. I could've jump started it from my wife's car but... it was just much easier to take the bike.
Nearly -5F outside (or -20C). And yes, it's only 61F (16C) in my kitchen at 6AM but I like it that way.

When it comes to riding a bicycle in winter it's not the air temperature that matters but exposure, defined as the outside temperature multiplied by the time spent on bike. And this means that even when it's really freezing outside, but you only have to bike to the grocery store 2 blocks away, you will likely be fine wearing your regular winter clothes. You won't freeze to death before you reach your destination anyway.

However, rides that take about an hour or maybe even longer, require some more preparation. The three most important parts of your body to take care of during such rides are:

Hands
Unlike the core of your body that will likely stay cozy warm due to extra heat you produce on bike, your fingers may start to freeze. Except of operating brakes and shifters occasionally, fingers grasp on the handlebars and don't move. Also, they are exposed to wind chill, so ideal winter gloves should not only be insulated but also wind/water proof. After years of experimenting with double gloves, liners, bike-specific ones, etc., I decided to spend some more to get more and bought Hestra Army Leather C-Zone mittens. At $108 a pair (after discount), they were not exactly cheap but well worth the money. Being a 3-finger mittens they are much warmer than anything I tried before, yet still let me operate brakes and shifters with ease. Add to it a lot of insulation and waterproofing and you get a glove for those freezing winter rides. I have been using them for the last month and noticed that at temperatures above 22F (-5C) they are just too warm. But whatever mittens you buy get a pair a size too large. The extra pocket of air will help keeping your fingers warm.

Feet
Keeping your fingers warm is easy compared to protecting your toes. You (rarely) move your fingers when biking but when it comes to your toes, they stay still all the time. And that means that sooner or later (likely sooner) they will start to freeze. I haven't found a 100% perfect solution except of cheating with some chemical toe warmers. But after I switched to North Face Snowsquall Mid my toes stayed warmer for much longer. In fact, the best test of these boots happened just this morning. I usually take a shortcut through a forested area in Bedford, next to some industrial buildings and a parking lot. Last night that place was fully passable but this morning it was flooded, with its top layer frozen. Could it be from a burst pipe somewhere nearby? All this means I had to walk through this puddle of icy water that turned out to be a 3-4 inches deep. Fortunately, my boots survived this treatment easily but stayed iced for the remainder of the ride. Good that Snowsqualls are waterproof. I wouldn't want to have wet feet at -5F weather.

Head
Your ears need special care at these temperatures so cover them well. I use a fleece headband, a thin wool hat and a helmet. The helmet is obviously the least important part of this puzzle but I wear it because it reduces wind chill pretty well. You may want to replace it with a thicker hat if you like.

Covering face is tricky and in general I don't like full-face balaclavas. They are too warm for me for most conditions. If you decide to get one, I suggest you look at models with nose and mouth holes. Without these openings your balaclava will soon be completely frosted with iced water vapor you exhale.

My solution to this problem is a thin, wool buff. I wear it to protect my neck (so no scarf needed) and I pull it over the back of my head (covers back of my neck) so it covers my cheeks (at least partially) from both sides. This way the buff doesn't cover my mouth and nose yet still works quite well as I can quickly adjust it and pull it down from my face if I get too warm or pull it up over my nose if I encounter severe wind chill.

Over the course of the last 4 winters I found out that the most difficult face part to protect from severe wind chill are the cheeks right over the cheek bones. In those places the skin is very thin and bones underneath act like a heatsink, which means your skin cools down there very quickly. The only good solutions are either a full-face balaclava or those funky pieces of tape, professional cross-country skiers use. Neither of which seems terribly attractive to me.

That's it. The rest of your body is much easier to take care of. Rule #1 is not to overdress. If you get sweaty and face severe wind chill you're asking for trouble. I usually end up wearing only my regular work shirt plus a wool sweater (a thicker one for those subzero rides). Then I wear a waterproof hardshell over it. The hardshell is there only to cut off any wind chill from my body.

Even in subzero conditions I don't use any special insulated pants - just my regular work chinos. But because wind chill can make my ride very unpleasant, I put a second layer on - waterproof cycling pants I got at REI for $25. They don't let any air through, so my legs stay toasty warm for the entire ride and they are easy to remove at destination pretty much anywhere. No need for a private changing room.

This morning ride was much easier than I expected. No wind chill and low humidity resulted in surprisingly pleasant conditions, despite -5F on the thermometer. In fact, I remember a day about 2 years ago that was easily 10 degrees warmer, but my cheeks and toes were pretty much frozen when I arrived to work. Wind chill does make a huge difference.

Nevertheless, I was stopped by a driver in Bedford who must've felt sorry for me when she asked if I needed a ride. It may be difficult to believe for some people but -5F on a calm winter day is actually perfectly appropriate for bike riding.

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