Salmon is a hunting and recreation gateway on the edge of the Frank Church-River of No Return Wilderness, a town steeped in Western lore and known as the birthplace of Sacagawea. My trip began at the Hub, a new bike and ski shop a block off Main Street that also serves pizza and beer. There I met the owner, Max Lohmeyer, a Fruita, Colo., native and lifelong mountain biker, who would take me for an evening ride on Discovery Hill. After exiting Mr. Lohmeyer’s van at the trailhead, we crunched on our bikes over thin patches of snow turned ice luge in some sections. In the dark, chips of snow that shot from the front tire glowed like welding sparks as they floated through the bright beam of my bike light. Traction on marginally snow-covered trails varied with pitch and aspect. Navigating surfaces and slopes was more fun than it may sound, which I attribute to the novelty of riding a super-fat mountain bike tire under the shine of a full moon. At times during our ride, some 13 miles through mountain desert country with the Salmon photographer David Lingle, we could see the lights of town below.
Back at the trailhead another rider left a note on Mr. Lingle’s car, a calendar photo of two emperor penguins standing together in the grass. One bird, craning its neck, had a scribbled dialogue bubble above it that read, “Just call me Master of the Moonlight! Bahahaha.”
A fat bike rider descends through the backcountry to Baker Creek trailhead, north of Ketchum, Idaho.CreditDavid Lingle for The New York Times
Later, at dinner at the Junkyard Bistro in Salmon, where the special was an Idaho burrito with mashed potatoes and bacon, the conversation was, inevitably, about fat bikes. “I’ve never seen a trend come on so fast,” Mr. Lohmeyer said. (So much so that the first-ever U.S. National Fat Bike Championship will be held March 8 in Cable, Wis.)
In bed after enjoying the frontier night life, which included watching outdoor hockey, my mind continued to slip and slide — I was hooked on riding in the snow and excited to try it in the daytime too.
To get to my next destination I drove through the wide valleys of the Lost River and Pahsimeroi mountain ranges to the Teton Valley, which has a large contingent of snow-sports people in the towns of Victor and Driggs. Snow biking is managed in conjunction with Nordic skiing at the base area of the Grand Targhee Resort at 8,000 feet in Alta, Wyo., and just over the border from Driggs. Groomed trails wind through the forest nestled in the backdrop of the Grand Tetons.
At Grand Targhee, I was unable to resist the temptation to jump into a fat-bike race on a custom Trek Farley that I tested from Fitzgerald’s Bicycles in Victor. (It’s the first year that Trek, based in Wisconsin, has produced a fat bike; the Surly Pugsley from Minnesota is known as the first mass-produced mountain bike with extremely high volume tires.)
“Fat biking is exploding,” said Andy Williams, who organizes special events at the resort and is developing a single-track grooming mechanism to tow behind a snowmobile to further expand snow biking. “It’s really a great way to get out and enjoy winter,” he added, explaining that other groups, including Nordic skiers, are beginning to wrap their heads around the new use of trails. “It’s not a bad thing, just different,” he said. “Fat bikers and skate skiers almost go the same speed.”