Mountain biking is a huge part of life for Jay Bollinger, his wife Krista, and their two school-age sons. The family lives just a couple of blocks from South Table Mountain in Golden, a haven for mountain biking, and their oldest boy, Isaac, competes on a mountain bike racing team.
Krista hadn’t been able to ride with them in recent years, though, as she battled breast cancer and endured strength-sapping post-operative treatments. Then, Jay bought her an e-mountain bike last fall, and for the first time in years, the four of them could hit the trails together.
“We went to South Table, and it was so awesome,” Krista said. “I hadn’t been on my mountain bike in forever. I just didn’t have the confidence that I could handle it. It’s not like [the e-bike] gives me this super extra [boost], but I can go up hills and hang with them. We can all enjoy it.”
E-mountain bikes, which have become a major segment of the cycling market, have electrical assist motors just like e-bikes designed for roads, but they also have the fat tires and shock-absorbing suspension systems that are common in human-powered mountain bikes.
At Wheat Ridge Cyclery, about four out of 10 customers shopping for e-bikes are looking for rides they can take on trails, said store marketing director Jason Sommerville. “Year over year, we’ve sold double the amount of e-bikes versus 2022. Supply is catching up, technology is catching up. We’re getting lighter, quieter e-bikes. “
But that popularity has led to grousing from traditional mountain bikers when it comes to e-mountain bikes, and public land managers across the Front Range are still working through which e-bikes to allow where.
Rules of the road
E-bikes, whether designed for roads or trails, come in three classifications as defined by the Colorado legislature in 2017, and those distinctions determine where their use is allowed.
Class 1 e-bikes have motors that provide propulsion assistance only when the rider is pedaling, and they cease to assist when the bike reaches 20 mph. Class 2 e-bikes also stop assisting at 20 mph, but they assist whether the rider is pedaling or not, and they have throttles. Class 3 e-bikes assist when the rider is pedaling but stop helping when the bike reaches 28 mph.
Jefferson County Open Space moved early to welcome e-mountain bikes in 2018, but not before surveying hundreds of park users for their opinions and concerns. Based on those surveys, the county decided to allow only Class 1 bikes on its trails.
“There was no tolerance in our visitors for something with a throttle on a natural-surface trail,” said Mary Ann Bonnell, Jeffco Open Space visitor services and natural resources director.
“We heard that loud and clear,” she added. “We do not allow the Class 2, where you can have the power without pedaling. People said, ‘Nope, don’t want to see it. Don’t want to see someone flying up a hill and not pedaling.’”
But after five years, the county hasn’t found that e-bikes increased conflicts or created safety concerns, Bonnell said. “People continue to fall and have crashes on their mountain bikes, we continue to field complaints about conflicts, but they are not tied specifically to e-bikes.”
In national forests, e-bikes are considered motor vehicles, so they are allowed only on roads and trails designated for motorized use. In Rocky Mountain National Park, e-mountain bikes can only go on roads where motor vehicles are allowed, paved or dirt. (It should be noted that human-powered mountain bikes are not allowed on the park’s hiking trails, either, with one small exception on the west side of the park.) In Colorado state parks, Class 1 and 2 e-bikes are allowed on roadways, designated bike lanes, and multi-use trails open to non-motorized cycling.
Boulder County Open Space allows Class 1 and Class 2 e-bikes on its flatland trails, and has since 2019, but neither are allowed on its mountain trails. But the city only started allowing Class 1 and Class 2 e-bikes on 39 miles of its 155-mile open-space trail system this month.
“As e-bikes were not allowed on city open space trails before July 1, we do not have statistically valid data for e-bike use on open space trails,” said Phillip Yates, a spokesman for Boulder Open Space and Mountain Parks, via email. “E-biking will be added as a new category in future visitor surveys, alongside all other allowed activities, to track change over time as part of system monitoring. That will allow staff to report out changes, if any, that may be attributed to e-biking activity on the open space visitor experience.”
A wider issue
The difference in how park and open space managers regulate e-mountain bikes reflects what is happening in Front Range municipalities. Denver allows all three types of e-bikes on bike paths, but with speed limits of 15 mph. Arvada passed an ordinance in January of 2021, allowing Class 1 and Class 2 e-bikes on its bike paths. Lakewood allows Class 1 and Class 2 bikes on bike paths. Class 1 e-bikes are allowed on Lakewood’s soft surface trails, including at Bear Creek Lake Park and at William Fredrick Hayden Park on Green Mountain.
Before making its decision, Jeffco Open Space interviewed more than 400 visitors in five parks in 2017 to glean their thoughts about the issue. The agency also sent out volunteers on e-mountain bikes, then asked visitors if they had noticed any e-bikes on the trail, and many said no. Satisfied that the presence of e-mountain bikes would have minimal impact on other users, Jeffco moved forward with e-bikes as a pilot program in 2018 and updated its park regulations the following year to make it permanent.
“Every time it comes up, I have this sigh of relief that we took care of this in 2017, because I feel really good about how we made the decision,” Bonnell said. “We did a ton of data collection, getting in people’s heads, public meetings, meeting with stakeholders. I really feel like we did a thorough job. I feel good about the decision, and I also feel like it has played out well.”
Some visitors raised concerns that people on e-mountain bikes would get lost, or injured, or would call rangers for assistance with dead batteries miles from the trailhead. “That hasn’t happened,” Bonnell said. “Conflict continues between riders and runners and hikers, but it’s not e-bike-related conflict.”
Gary Moore, executive director of the Colorado Mountain Bike Association, said while some mountain bikers have expressed displeasure on social media statewide, the impact of e-mountain bikers on trails has been negligible.
“Any conflicts between trail visitors continue to be more of a matter of the people themselves,” he said, “rather than their preferred mode of travel. You see them pretty much anytime you go out now.”
Meanwhile, Jay Bollinger loves having his wife with him and their boys, who are 10 and 15, on the trails.
“It’s been really good,” he said. “She’s still regaining her skills, but it allows her to keep up, rather than being the one who’s slowing everybody down.”
He sees the way e-mountain bikes have made it possible for older cyclists to ride the trails he loves. He’s even thinking he may be a candidate for an e-mountain bike someday.
“They can do multiple laps on a trail that just wouldn’t be possible for them on a regular mountain bike,” he said. “Down the road, when I no longer have the strength to ride up stuff like I used to, it will extend my ability to enjoy mountain biking.”
