After decades of experience riding a bike in winter, here is the definitive guide to keeping hands warm on a bike in winter.
Not Just an Ad.
Cold hands is the most common form of discomfort in winter cycling so keeping hands warm on a bike in winter is worth putting some effort into. Yes, I sell pogies, and yes, I want to talk about them, but, I’m here to help, not just sell my fine hand crafted wares.
Let’s Head to the Bar!
There are 2 important factors to handlebars. The first and most important is its thermal conductivity, this is how fast it draws the heat from your fingers. The second is thermal mass, the amount of mass that your finger heat is going to have to heat up before the heat stops getting drawn out of your fingers.
Lots of bicycle handlebars are metal, mostly aluminum. Now, aluminum is strong, and light, but it is also a great conductor of heat. It has mass, and probably has some exposed surface to shed conducted heat into the air. In electronics hardware design (my “real” career), we often use aluminum heat sinks to shed heat from ICs into the air. This same thing happens with bikes, except the heat comes from our hands, where we want to keep it, at least in winter.
So What Helps?
Carbon fibre, the secret bike industry code word for “really expensive” is, also, a poor conductor of heat, and has less mass than aluminum. Now in the winter cycling context, the really important part is the lower conductivity. Carbon fibre is somewhere around 0.3% the thermal conductivity of aluminum, so even if you buy the heaviest carbon fibre bar, the mass won’t matter. Shaving grams won’t make your hands warmer.
Whoah, Those Carbon Bars are Pricey, and I Hear They Break![update below: measured numbers]
I did some testing this winter at -9ºC with carbon and aluminum bars, and even with the tricks mentioned below, the carbon bars make some difference. There was a 1.5º difference in the temperature of my grips between 1-Up carbon bars and Jones Aluminum H-bars after a 25 minute ride. Both had the same grips, brakes, and similar levers. Though I could not feel a difference in my hands, this might be a significant difference in more significant cold, or on longer rides. Temperatures outside the pogies on the bars were about half a degree warmer on the aluminum bars, so I am comfortable saying that at least some of the difference is from conduction.
Carbon bars are pricey, they cost more than some people’s bikes. The cheap ones from sources with dubious quality control are not something I’d rely on, especially for riding below -20ºC. I know several people who have broken cheap carbon bars. Good carbon bars are an excellent choice though, for anyone who wants to ride long distances, or in extreme cold, or who just likes the more comfortable ride quality.
If you already have metal bars that you like, or don’t trust the crappy cheap ones from online sources like this Amazon Associate Search or ones that you find in a real bike store don’t appeal to you, there is still hope.
It’s a Wrap!
Neoprene, packing foam, upcycled beer cozies, are all great insulators. Wrap them around your grips, and cover them in heat shrink tubing like this amazon associate link, and you’ve got a great thermal break between your grips and your hands. The grips themselves do help, but rubber, especially silicone rubber does conduct some heat, so it really helps to give them a boost.
If all else fails, a double wrap of bar tape is a good solution that gets you at least 70% of the way to bars that don’t suck (heat).
My Mom Always Told Me to Wear my Mittens!
Once the bars are taken care of, you can put your mitts on and call it a day right? Right, until you want to shift gears, and support your friend Doug who sews pogies, not mittens.
Really though, mittens are great. If you are going riding in the cold infrequently, have gears that are easy to work with mitts on, or don’t want pogies.
Tell me About Pogies!
Mittens that stay on your bike mean that you can pull your hand out to flip the bird, and whoever you are waving to can tell that your uncovered middle finger is up. They mean that you can have light gloves or bare hands, so if you decide to check your phone, you can work it. If you want to take a video, pull out your camera and go, because you don’t have to remove and stow your mitts to do it.
Aside from the dexterity, pogies are way bigger than mittens. That’s not that great until you realize that you can fit way more insulation in a pogie than you can in a reasonable mitten. Pogies are warmer. They are handy in other ways too. Though the ones I make currently won’t hold a family sized bag of Cheetos like the ones I made for the ITI, you can certainly still fit granola bars and other snacks in them and prevent breaking teeth on frozen food.
Sometimes, mitts and gloves can have cuffs that will restrict blood flow to the hands. This can also be a disadvantage to keeping hands warm since slower blood flow is also slower heat flow. The circulatory system is the body’s main mechanism for heat transport.
The Overlooked Parts:
While stopping heat loss to the bars, and insulating the hands is great, they aren’t the only things that affect keeping hands warm on a bike in winter.
The first thing the human body does when core temperature starts to drop is to cut off circulation to the extremities. That’s right, if your body gets cold, you’ll stop warming up your hands with warm blood. This can be a bit of a vicious circle when your core gets cold from cold blood returning to your chest after cooling in your hands. Again, experience has taught me that this can be improved by keeping the core warm enough not to trigger this reaction (but not enough to sweat) , and to try not to lose so much heat on the way to and from the hands. A great way to do this is to chose pogies with longer cuffs, like mine.
Breathing warm air can keep your hands warm on a bike in winter?
My article on Heat Exchanger Masks talks a lot about preventing heat loss through the lungs. This heat retention helps keep blood moving to the hands. I also find that if I keep the blood from cooling in my forearms, it helps to keep my hands warm, and again helps prevent the body’s reaction to cold of slowing down extremity circulation.
What About Heat Packs, Or Electric Mitts
I spent a bunch of money on heat packs in the ’90s I liked them, but they violated a few of the things I talked about above, where they created a cycle of slowing circulation and ended up not warming my hands that much. If your core, has cold blood returning to it from extremities, it will slow the circulation to the extremities unless the core has enough heat to lose. Warm hands without circulation don’t work much better than cold hands, so the net is a loss. Hand warmers are no match for good insulation and circulation.
Also, keep in mind that I focus a lot on winter bikepacking, and so I would much rather carry an extra 360g of pogies than 3 pounds of hand warmers, or gloves and batteries.
But My Circulation is Bad!
There are a bunch of reasons why poor circulation to the hands can happen. I don’t know the magic required to cure Raynaud’s Syndrome, or any of the circulatory disorders that challenge many people. I am not a doctor. I make the warmest pogies, but even these are not magic. Anecdotally, I have heard from a few people that by following my recommendations and using my Ray-no-Luke Extreme pogies, their hands are the warmest they’ve been on a bike. Raynaud’s syndrome is also a case where external heat packs are beneficial, it is not just slow circulation, and does not respond as well to warming as most circulatory conditions.