Electric Mountain Bikes Are Finally Fun to Ride
New, more-refined designs have made these pedal-assist machines significantly more appealing
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As part of our bike test this year, we decided to include three electric mountain bikes, fully prepared for the protests and vitriol from our readers. Every time I’ve written about this growing trend, it becomes clear that a contingent of people detest pedal-assist bikes—some on principle, some because they fear these bikes may lead to trail access issues, and some seemingly out of knee-jerk puritanism. The most common refrain seems to be that e-MTBs are motorized vehicles, not bikes. “Motor + Bike = Motorbike. Duh!” one reader commented on a story I wrote.
This objection, however, misses the finer distinctions: the bikes we tested are all of the pedal-assist variety, meaning there’s no throttle and no motor assistance unless you pedal. “The comparison to motorcycles is just wrong,” says Sean Estes, global PR manager at Specialized. “The [Specialized Levo eMTB] produces a peak power output of 530 watts, while a KTM 250cc four-stroke motorcycle produces roughly 32,000 watts. Considering power-to-weight ratio, the Levo essentially gives every rider around 6.5 watts per kilo, on par with a Tour de France–level cyclist. That’s a big bump but nowhere near the same galaxy as a motorcycle.”
Everyone is entitled to their opinion, but the criticisms aren’t going to stop the growth of these bikes. In the past few years, all the major brands have introduced e-bikes, which speaks to the market’s potential. You can bet that companies like Giant, Scott, Trek, and Specialized aren’t dumping money into development and tooling unless they believe e-bikes are here to stay.
The entry of mainstream brands has also been good for the segment, both for the credibility these companies lend and for their engineering and design know-how. Some of the first e-MTBs that I rode had good power trains, but their trail manners were clunky and maladroit. The latest designs, however, have real mountain bike DNA, and they ride like it. This is the crux of why e-MTBs aren’t going away: they are an absolute riot to ride.
Before you begin trashing me, I’m no lazy, motor-dependent, entitled American. I rarely drive my car if there’s the opportunity to ride a bike. I train five to six days a week, race on road and dirt, and generally prefer endurance endeavors that make most people shake their heads (think: AZT, Dirty Kanza, and Vapor Trail). Still, I’ve had a hell of a good time on the e-bikes we’ve been testing.
If you ride a lot, you know it’s exhilarating to smash along on dirt as fast as you can go—some extra power just makes it more bracing. The hauling capacity on these bikes is a boon: hooked up to a BOB trailer (courtesy of the awesome Robert Axle Project adapter), the Levo has helped me transport camping gear, rifle, pack, and an entire field-dressed deer some ten miles in one go.
Then there are the days when an e-bike motivates you to ride when you otherwise might not. A few months ago, a friend and I did a five-hour ride on a Saturday with 7,000 feet of climbing. Afterward, he was on the fence for the Sunday ride because he felt it was too much. I lent him an e-MTB, and we pulled off another four-hour epic together, when otherwise I would have ridden alone. We all have those days when we feel too tired or stressed to ride—add a little pedal assist, and the threshold for getting out is lower.
That doesn’t even get into these bikes’ potential to bridge ability gaps (for instance, my once fit but now ailing 64-year-old father-in-law and I can ride together again), lower the hurdles for new riders (because it can be intimidating to start out), and help those with disabilities enjoy our great sport.
In other words, we decided to test these bikes this year because there are a lot of upsides. Here’s a brief rundown of the three we tried.
Haibike XDuro AllMtn 8.0 ($7,000)
Before any of the big brands jumped into the game, Haibike was selling and advocating for e-MTBs, which gives the company market cred. This 150mm 27.5+ machine was the biggest and burliest in the test, with a stout, inverted Magura Boltron fork and, at 52 pounds, the heftiest weight. The bike uses a 350-watt Bosch Performance Drive Unit paired with a 500-watt-hour battery. Our tester came set to European standards, meaning assist maxed out at 14 miles per hour rather than the 20 mph U.S. limit. (The AllMtn is for sale here in the United States with the faster motor.) The bike was sluggish but had plenty of low-speed torque, which made it easy to get up even the steepest, rockiest pitches. Side note: the debate about whether these bikes are allowed on trails may eventually hinge on max assisted speed, with some critics arguing that faster bikes could be dangerous.
The AllMtn has all the specs you’d want: Fox Float fork, SRAM EX1 drivetrain, KS Lev Dropper, 2.8-inch Nobby Nic tires. But it also has the steepest head angle, the tallest stack, and the shortest reach, all of which combined to make it feel upright and a bit awkward on the trail. The suspension worked well enough, and we liked the rigid certainty of the fork, but overall the bike felt the least deft of the three.
Trek Powerfly 8 FS Plus ($5,000)
This bike pairs the same Bosch motor and battery as the Haibike to a more manageable 130mm trail-oriented bike. That might not sound like a lot of suspension, but honestly it’s as much as you need for most situations. As on the Haibike, a two-button controller on the left toggles between four power levels, which display on the head unit: Eco (50 percent assist), Tour (120 percent), Sport (210 percent), and Turbo (300 percent). It’s a simple system, making it easy to constantly shift between modes, which helps with economizing battery power. Range will always depend on power level and terrain, but on a three-hour ride predominantly in Eco setting, I used only about half the battery power. Compared with the Specialized system, the Bosch motor feels like it has more torque, which is great for steep stuff but also means the bike can surge and feel like it gets away from you a little in the higher power modes.
Despite the 50-pound weight, the Powerfly mostly rides like a capable mountain bike, with Trek’s supple rear end and an excellent Shimano XT 1×11 drivetrain. While I sometimes like the 2.8-inch Bontrager Chupacabra tires, here the rounded profile and low-profile tread don’t feel meaty enough for the weight and power. The fact that we were parsing details like this speaks to just how capable and refined the ride quality is—it feels like a normal mountain bike with the added benefit of pedal assist. Given that it’s the least expensive in the bunch, it’s difficult to argue against the Powerfly.
Specialized Turbo Levo FSR Expert 6Fattie ($7,500)
In simplest terms, this bike is an electrified version of the 2016 Gear of the Year–winning Stumpy FSR 6Fattie, so it should come as no surprise that we loved it. The 530-watt Brose-built motor and 504-watt-hour battery are proprietary to Specialized. Though the system doesn’t have quite the torque of the Bosch, it still has ample power for getting up anything, and a few testers preferred the way it ramped into the speed rather than gunned it. While cruising on flats and rollers, testers with smooth pedal strokes noted a slight choppiness in the power, almost as if it was cutting in and out.
On the other hand, we loved the low profile, with the on-off switch and power-level indicator placed inconspicuously on the side of the down tube and the battery and motor concealed by the oversize bottom bracket. Power comes in three stages—25 percent for Eco, 50 percent for Trail, and 100 percent for Turbo—which you change with two buttons near the power switch. While we like the clean looks, the lack of a handlebar controller makes it tougher to toggle between levels (though the system is customizable via smartphone and compatible with a Garmin Remote). Like the Trek, max assist speed is 20 mph, making the Levo feel very fast. We also found that fit riders preferred riding mostly in Eco mode, which provides just enough boost to take the edge off (and keeps you ahead of most riders) but still provides a workout. On Eco, four hours of rugged trail riding used 60 percent of the battery.
As with all of these bikes, the longer wheelbase (1.25 inches for the Specialized) made tight handling and steep switchbacks a little trickier. For the most part, though, the Levo feels like a souped-up Stumpy, but the position is slightly more upright, and the 140mm front and rear travel is a bit off as well. (And it weighs 50.5 pounds.) The Specialized feels more capable and forgiving than the Trek in the rough stuff, perhaps because of the longer suspension and the excellent, aggressive three-inch knobby Purgatory Grid tires. The spec is a slight upgrade over the Trek, too, with a RockShox Pike instead of a Yari and a Fox Float factory shock. That said, you pay a hefty premium for those upgrades: for flat-out performance, the 6Fattie was our favorite, but with price factored in, testers leaned toward the Powerfly.
Cost is still an impediment to e-bikes catching on. While most testers liked these bikes, they agreed they’d be hard-pressed to buy one as a secondary ride. As a primary bike, however, the prices are mostly on par with the general mountain bike market, and now that performance has caught up, e-MTBs are a realistic option for everyday riding. Prices should continue to drop as technologies advance and the market grows.
The other big consideration is trail access and legislation. “States and municipalities don’t generally have clear definitions of e-bikes. Some allow them, some don’t,” says Morgan Lommele* of People for Bikes. State parks in a handful of states (including Colorado, Pennsylvania, Florida, and North Carolina) permit e-MTBs anywhere bikes can go. But on federal lands, including those managed by the U.S. Forest Service and the Bureau of Land Management, e-MTBs are “considered motorized vehicles,” Lommele says, meaning they have access only to motorized trails. Advocacy efforts are underway to standardize e-MTB designations along similar lines as street-variety e-bikes. There’s also a push to get federal trails to include e-bike designations.
These distinctions didn’t matter that much a few years ago, when electric mountain bikes weren’t that great and few of them were around. With the current crop of excellent new bikes, however, the technology has outgrown the legislation, leaving e-MTB owners to work through a disparate web of rules and police themselves. (People for Bikes has some helpful resources.) All of this uncertainty makes it a fascinating, and potentially tricky, time to own an e-MTB. But one thing is certain: with the advances in e-MTB design and technology, the regulations need to be sorted out forthwith, because these bikes are so entertaining and refined that they are not going away.