When Mammoth Mountain Bike Park opens for the 2019 season—a date that has been pushed back due to late winter storms—riders will be able to explore the California resort’s trail network not only aboard standard mountain bikes, but also using electric-assist models.

This is the second season that pedal-assist mountain bikes, or electric mountain bikes, will be allowed in the park. The policy was precedent-setting when it was enacted a year ago: Up until then, e-bikes, classified as motorized vehicles under the federal Travel Management Rule, were excluded from use on most trails on U.S. Forest Service land, in national parks and other federal lands. The success and extension of the program at Mammoth this year and the spread of similar arrangements at mountain bike parks around the country signal the continuing proliferation and acceptance of e-bikes.

Like many ski resorts, Mammoth leases its land, some 3,500 acres, from the U.S. Forest Service, and operates under a special-use permit that allows it to develop ski runs and trails and install infrastructure such as lifts and snowmaking. The path toward e-MTBs began four years ago, when Mammoth approached the USFS to clarify whether its permit allowed for e-bikes, despite the USFS decision to manage them as motorized vehicles. The resort was greenlighted in 2016 for an e-bike category in an event called The Boogaloo at its annual Kamikaze Games. That limited use was instrumental in proving that e-MTBs didn’t have any more impact than standard mountain bikes on Mammoth’s 80 miles of singletrack, thus shepherding their widespread adoption in 2018.

“The special-use permit issued to Mammoth demonstrated that e-MTBs can exist in harmony with mountain bikes and allow families and friends of varying abilities to go out and have a great time on the mountain together,” said Larry Pizzi, vice president and chair of the e-bike committee for the Bicycle Products Suppliers Association (BPSA).

Whether or not e-bikes belong on trails has been one of the most hotly contested subjects in cycling in recent years, with opponents worried that faster-moving and heavier bikes will cause more trail damage and user conflicts, put inexperienced riders at jeopardy by allowing them to outride their skills, and lead to trail closures. “There has been a segment of people opposed to them, though attitudes are shifting with increased exposure and education,” Pizzi said.

What some people don’t realize is just how similar some electric-assist mountain bikes are to their analog counterparts.

“There is a lot of misinformation,” said Janelle Walker, the U.S. Forest Service representative who oversaw the approval process at Mammoth. “Generally the public is not aware of the different classes of e-bikes and that leads to the assumption that they are more similar to motorcycles [than bicycles].”

At Mammoth, the permit allows for Class 1 e-bikes, which have a max assisted speed of 20 mph and provide supplemental power only when a rider is pedaling. It precludes more powerful bikes and those with throttles. Because these bikes must be pedaled to function, “they perform comparably to a regular pedal bicycle,” Walker said.

As the numbers of e-bikes in the field increase, more people—both cyclists and legislators—are realizing that they bear far more resemblance to bicycles than motorcycles. An environmental impact study carried out by the International Mountain Bicycling Association (IMBA) found that Class 1 e-mountain bikes “were not significantly different” than conventional mountain bikes when it came to soil displacement and tread disturbance. IMBA has since updated its position from its initial 2015 stance that e-bikes should be treated as motorized vehicles to current support for Class 1 models on mountain biking trails “when the responsible land management agency, in consultation with local mountain bikers, deem such e-MTB access is appropriate and will not cause any loss of access to non-motorized bikes.” That’s precisely the scenario at Mammoth Bike Park.

The effects of Mammoth’s e-mountain bike program have reached well beyond the park. “Our permitting process catalyzed the clarification of some USFS regulations,” said Gabe Taylor, head of marketing for Mammoth Bike Park. “It should have made it easier for other resorts to apply for and receive the same permissions we were granted.”

Few U.S. resorts have as extensive a setup as Mammoth, but e-MTBs are now being used at Mount Snow, Vermont; Highland Mountain Bike Park, New Hampshire; and both Steamboat and Purgatory, Colorado; among others, with many resorts now eyeing adoption. According to Earl Saline, director of education programming at the National Ski Areas Association (NSAA), an increasing number of resorts are moving to invest in year-round activities. While there’s no formalized list of resorts that have approved e-bike use, People For Bikes keeps an interactive map that’s constantly updated and land-manager approved of all the trails in the country open to e-MTBs.

The shift toward e-MTBs at bike parks mirrors the increase in their widespread acceptance. Numerous e-MTB-specific race series have cropped up, including the decision late last year by the Union Cycliste Internationale (UCI), professional cycling’s governing body, to hold the first-ever e-MTB World Championship in Mont-Saint-Anne, Québec, this August. Meanwhile, following a quarterly e-MTB roundtable with federal agencies on March 14, the BPSA said they expect the National Park Service (NPS) to reissue in the next few months revised guidance on electric bikes that will allow greater leniency in the interpretation of Class 1 and 3 e-bikes as bicycles. In a memo, Pizzi, the chair of the e-bike committee at BPSA, said the Bureau of Land Management (BLM) is considering following suit and the National Forest Service is apparently under pressure from the National Ski Areas Association to create a new definition of e-bikes separate from motorized vehicles. These policy shifts could be the first moves toward e-MTBs gaining access not only at bike parks, but on a wide swath of public lands.

“It’s unfolding as we speak,” said Pizzi.

At Mammoth, demand for e-MTBs has been brisk. The resort has a fleet of the bikes for its staff, which has allowed for easier and more frequent trail maintenance and allowed for faster response times for on-hill incidents. Pedal-assist bikes also now account for 30 percent of the mountain’s rental fleet.

“Mountain biking is hard work, especially at our elevation (9,000 to 11,000 feet). For a lot of guests that’s just more than they’re up for,” Taylor said. “E-bikes lower the physical barriers to entry and make it easier for more people to enjoy more of the terrain.”

And e-MTBs aren’t just grabbing market share from standard bikes, but rather adding to it.

“E-bikes offer an activity that family members of all ages and abilities can do together,” said Steve McCabe, director of mountain operations, who spearheaded the e-MTB initiative on the mountain. “Put simply, e-bikes are allowing more people to enjoy mountain biking.”

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