Snowy weather generally signals the end of mountain biking season—unless, of course, you have a fat tire bike. Wide, lugged tires make fat bikes highly capable in the snow. For cyclists used to wheeling in warm weather, fat bikes can open up a whole new season for riding. In fact, fat biking can help you actually enjoy winter.
Fat biking is relatively easy for beginners to pick up. But riding a fat tire bike in winter conditions carries some important differences from mountain biking in the summer. Experts John Roe, Fatbike Committee Chair for the Northern Michigan Mountain Bike Association and Aaron Ruff, President of the Central Wisconsin Offroad Cycling Coalition, weigh in with advice on everything from gear to tackling the trail. Here’s what you need to know before you head out on knobby wheels this winter.
What Makes a Fat Tire Bike?
As the name implies, fat bikes are primarily defined by their burly tires. Both Roe and Ruff agree that a 3.8-inch tire is the accepted minimum for a fat bike. Wider-width tires make for excellent winter riding.
“Wide tires enhance the flotation on the snow,” Ruff says. “If you were to ride a regular mountain bike on a snow bike trail, you’re going to put a big rut right through it.”
In addition, most fat tire bikes are hardtails without front suspension. That’s because they’re primarily designed for snow-covered trails where rocks and roots are less exposed. Snow creates a smoother trail surface, lessening the need for shock absorbers.
Where to Ride
Navigating in wintry weather can be difficult, but Gaia GPS can help. Check out the Open Cycle, Gaia Topo, and USFS maps to get a sense of paths, dirt roads, and trails in your area. Look at the continuously updated satellite imagery layers to see if there’s snow on the ground. You can even map out a route beforehand.
The app’s real-time GPS navigation will keep you on the trail even when it’s covered in snow. Plus, you can download unique map layers, like snow depth maps, to get a better read on trail conditions. Record a track in the Gaia GPS app to monitor stats like pace and distance and drop waypoints to mark trail junctions or where you parked your car. For more guidance on choosing a trail, see the “Trail Etiquette” section below.
The Gear You’ll Need
As with any winter sport, fat biking requires proper gear to keep you comfortable. Although your exact kit will depend on how far you ride, the weather, and your own cold tolerance, some general guidelines can help you prepare. The first will likely sound familiar: layer up.
Getting hot and sweaty on an uphill climb can leave you freezing — and potentially hypothermic — later on. To avoid getting cold after sweating, Ruff recommends wearing a moisture-wicking base layer, ski pants, and a windbreaker shell. Ride with a pannier or frame bag so you can pack extra layers or store them when you peel them off when you finally warm up. And you will warm up, says Roe, so don’t overdress.
“I always recommend starting a little bit cool, and then if after 10 or 15 minutes you’re not getting warmed up, then maybe add a layer,” he says. “You don’t want to start comfortable because then you will be too hot.”
You’ll also need to protect your hands, feet, and face. A good pair of winter boots will work for fat biking, Roe says. Some companies make clipless boots; but that’s an upgrade, not a necessity. A good pair of insulated ski gloves will keep your hands warm, and you could also try pogies, which attach to the handlebars and allow you to wear lighter gloves (or none at all!). They also make it easier to use brake levers and shifters. Finally, add a face mask or neck gaiter to your kit, especially on windy days.
If you only get one thing right while fat biking, make sure it’s your tire pressure. Because of their large volume, fat bike tires can be run at very low pressures. Low pressure allows the tires to “mushroom” out beneath you, float over the snow, and get optimal traction, Roe says. Over-inflated tires sink into snow, which makes riding difficult.
In firmer conditions, like a well groomed trail, aim for roughly six to eight psi. In softer conditions, like powdery or mushy snow, aim for two to three psi, says Ruff. In both situations, heavier riders might need more inflation. Regardless of the exact snow conditions, both Ruff and Roe agree — you’ll never need to go above 10 psi.
A difference in even one psi can be noticeable. And it’s easy to tell if your tires have too much air: you’ll make a rut in the snow. If that happens, stop and let out more air until your tires float over the trail.
Riding a Fat-Tire Bike
Fat biking isn’t that different from riding any other bike. But because of the unique tires and conditions you’ll ride in, there are a few things to keep in mind.
In snow, go easy on the brakes and make gentle, controlled turns. Roe advises to stay off the brakes and roll straight through icy patches. This will help you maintain traction and prevent sliding. Even so, Roe emphasizes that when properly inflated, fat bike tires generate excellent grip. Thanks to their aggressive lugs and large surface area coming in contact with the ground, fat tires can really bite into the snow.
Fat biking generally requires a slower pace and a higher cadence than mountain biking. Both Ruff and Roe advise against mashing the pedals in high gear for two reasons. First, you need to manage your exertion so you don’t sweat too much and freeze later. Second, hammering the pedals will cause your rear tire to slip. Settle into a steady pace and use your drivetrain to your advantage.
“You’re definitely going to be spinning more,” says Ruff. “Just be ready to get into low gears.”
Fat-Tire Biking Trail Etiquette
Aside from the usual considerations like respect other users and leave no trace, fat biking involves following a few other important rules.
First, make sure the trail you want to ride doesn’t have restrictions on fat bikes. Ruff and Roe recommend contacting local mountain biking or trail management organizations to see if trail systems allow fat biking. Some trails allow cyclists only on specific days. Roe recommends visiting your local bike shop for information, as well.
Many fat bike trails have multiple user types: nordic skiers, snowshoers, even snowmobilers. Ride in the middle on the firmest part of the trail, and don’t ride on nordic ski tracks (a set of parallel grooves). If you’re sharing a route with snowmobiles, use lights and reflective gear. Those are the basics. International Mountain Biking Association has additional guidelines for riding on different trails.
No matter what route you choose, preserve the snow surface. If you have to walk your bike, walk to the side of the trail. Most importantly, do not leave ruts. They’re difficult if not impossible to repair, even with grooming equipment.
“If you’re leaving ruts on a snow trail, lower your psi,” Ruff says. “If you’re still leaving ruts, turn around because all you’re going to do is chew up the trail.”
Firm, moist, packed snow makes the best riding surface. Roe recommends riding in temperatures of 32 degrees or below (ideally, 15 to 28 degrees). If the forecast predicts warmer temperatures, ride in the morning before the snow softens. Avoid hitting trails when they’re covered in over four inches of new snow. Instead, wait until other users have packed down the trail or it has been groomed.
Connect with Local Bike Shops and Organizations
Don’t let the cold temps and snow-specific rules scare you off. Trail management organizations and local bike shops make great resources for learning about where and when to ride. In addition, Roe and Ruff recommend starting out with group rides so you can learn from experienced fat bikers. Once you get the hang of it, you’ll see snow in a whole new light.