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E-bike motor trends: mid-drives vs. hub drives

Published August 24, 2022

A version of this article ran in the August issue of Bicycle Retailer & Industry News.

By Paul Tolme

(BRAIN) — When Specialized announced the re-launch of its Globe brand in May as an affordable electric bike purveyor focused on car-replacing transportation, the company released only one spy photo showing an e-bike obscured by cargo baskets and cactuses.

While the e-bike's frame was largely hidden, one of the bike's features clearly was visible: a rear hub motor.

Call it a sign of the rising respectability of the humble hub motor, which until recent years has been largely shunned in the brick-and-mortar e-bike marketplace. Electric bikes with mid-drive motors such as those made by Bosch, Shimano, Brose, and others largely have dominated showroom floors.

But that dynamic is changing, thanks to the lower cost of hub motors compared to mid-drives, and as legacy brands chase the cost-conscious consumers who have turned to Rad Power Bikes and other online sellers peddling sub-$2,000 e-bikes.

For Specialized, the decision to specify a hub motor rather than a costlier and more efficient mid-drive system on an e-bike created for the masses was "a no-brainer," says Erik Nohlin, lead designer for Globe. A good hub motor gives you "more bang for the buck."

The topic of what is better, hub drives or mid-drives, stirs strong opinions. But it's an apples-to-oranges comparison, says Ed Benjamin, chairman of the Light Electric Vehicle Association.

"When someone asks which is better, well that entirely depends on what you're doing with it," Benjamin said. "Mid-drives provide a higher-performance experience in every respect."

That's why mid-drives are ubiquitous on electric mountain bikes.

But many e-bike buyers have no interest in mountain biking. Cost is their primary consideration. "A much larger number of hub drives are sold in every market because they are less expensive," Benjamin said.

"Manufacturers don't have to build the frame around the motor. That may not be important to the consumer, but it's very important to the brand and the factory," Benjamin said. "If it's a hub motor, you can put it on just about any bike."

Benjamin said hub motors have a role to play in the effort to get more people to ride bikes rather than drive a car. Electric bikes made to ride across town to the grocery store don't need to have the same level of performance and efficiency as mountain or electric road bikes made for long rides.

"Hub motors make sense in the commuter market and for people who just want to go for a cruise in the evening," Benjamin said.

Along with Globe, REI's Co-op brand is among the e-bike makers turning to hub motors. REI recently launched the Co-op e1.1 with a Bafang hub motor. Price: $1,499.

Part of the Co-op brand's new "Generation e" line, which includes the $1,799 e1.2 that will have a more powerful Bafang hub motor, these are electric bikes for non-cyclists. Hitting those sub-$2,000 price points would have been virtually impossible if REI had specified a mid-drive motor.

REI offers a five-year warranty on Co-op e-bikes, which shows the company's confidence in the quality and reliability of the hub motors. "Bafang is becoming a trusted name in the game," said Heather Henderson, senior product manager for REI Co-op.

Hub motors provide propulsion by accelerating the wheel, while mid-drive motors increase the power of a rider's pedal stroke. For individuals seeking the best power-to-weight ratio from their e-bike system, mid-drives are the only way to go.

"Hub motors are roughly 30% efficient, while a mid-motor from Bosch is designed to run at about 70% to 80% efficiency," said e-bike drive system engineer Zach Krapfl, co-founder of VPL, which distributes Bosch motors in North America to small- and medium-sized brands.

"In the IBD world, mid-drives are still dominating because you get that better efficiency and better torque," Krapfl said.

The biggest barrier to more widespread use of mid-drives is their higher cost. But the cost of Bosch-equipped e-bikes is coming down due to the introduction of moderate assistance motors such as the Bosch's Active Line.

"We are starting to see more Bosch e-bikes in the $2,000 to $3,000 range," said Todd Sellden, director of business and product development for Gates Global Mobility, maker of the Gates Carbon Drive belt system.

Gazelle, for instance, sells its Medeo T9 City HMB for $2,400 with a Bosch Active Line system. Batch, a consumer-direct brand, offers a model with a Bosch mid-drive for $2,600.

"It's possible to manufacture and sell a Bosch e-bike for less than $2,000," Krapfl said. "I know it's doable, and that people are evaluating how to do it. Bosch is always looking at market trends and how they can best target that value proposition consumer."

Krapfl says these sub-$2,000 mid-drive e-bikes almost certainly would be sold direct-to-consumer. He said these e-bikes could hit the market within 18 months. With Bosch components, they would be serviceable by independent local bike shops. "There would be a revenue stream for IBDs in terms of service," Krapfl said.

The Dealer Perspective

"Customers who come in asking for mid-drives are usually experienced bicyclists who want an e-mountain bike or performance commuter," said Alex Dunn, general manager of Seattle E-Bike. "If they are asking about good warranties, light weight, serviceability, then we convince them to go for a mid-drive."

"When people ask, 'What's the cheapest thing you offer?' We point them to the hub motors," Dunn said.

Two or more years ago, Dunn estimates that about two-thirds of the e-bikes sold in his shop were mid-drives. Now it's roughly 50-50. "We are starting to see these nice sub-40-pound e-bikes with lightweight hub motors," Dunn said. He points to Cannondale's $2,500 Treadwell Neo with a Mahle hub motor as an example.

"Mahle is sold through QBP, and they provide good service and support," Dunn said. On the cheaper end, Seattle E-Bike sells the brand Magnum. "Magnum is our affordable hub motor brand, and they are based in Salt Lake City, so they are easy to reach, and they have great customer service."

Another curious trend Dunn sees is mid-drive e-bikes with throttles. Seattle E-Bike sells a model from Serfas called the eDash Plus, which has a Bafang mid-drive and throttle.

Throttles are another divisive topic. Eschewed in Europe, they are hugely popular in North America. "Despite all the efforts to say mid-drives are better, the U.S. market has shown a favoritism for throttles," said Don DiCostanzo, CEO of Pedego. "The customers have decided: They want hub motors with throttles."

Pedego helped build the popularity of e-bikes in North America by manufacturing and selling affordable hub motor e-bikes through its branded stores. So-called "cyclists" are not their customer base. Weekend recreational rides and occasional e-bike commuters are Pedego's demographic.

Maximum pedaling efficiency is not something that people using e-bikes to ride five miles to work or school are worried about, DiCostanzo said. For these customers, a hub motor e-bike is superior in terms of price — and because it puts less wear on the drivetrain, he said.

Pedego sells one mid-drive — a mountain bike that uses a Shimano STEPS mid-drive. "On a full-suspension mountain bike, mid-drives make sense," DiCostanza said. "But that's it."

Krapfl of VPL worries about the glut of cheaply made hub-driven e-bikes on the market, and the fact that many of those batteries and frames might end up in landfills.

That's why he only works with Bosch motors and why he is skeptical of claims that cheap hub-driven e-bikes are beneficial to either the environment or consumers.

"I'm most interested in the car-replacement potential of e-bikes. To be a car-replacing transportation e-bike, it must be dependable, and it must be serviceable," Krapfl said. "If they are not reliable, they are a Pinto. They suck. They catch on fire."

Chris Nolte — founder of Propel and has e-bike shops in New York City and Long Beach, California — said his customers are most interested in a quality powertrain and drivetrain. He sells a lot of Bosch mid-drive e-bikes with Gates belt drives and internally geared hubs. "For us, that's one of the most popular setups."

He dismisses the argument about mid-drives being too expensive. "If you are a high-mileage commuter, doing car-replacing commuting, a high-quality center drive makes a lot of sense. A center drive assists you in a way that is more intuitive, and it is more motivating to pedal, versus a hub motor that gives you a pushing sensation."

REI Co-op  spec'd its e1.1 with a Bafang hub motor.
Topics associated with this article: Electric bike, From the Magazine

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