On most days, Pastor David Shinn carries out his high calling with the help of a car. Like 78 percent of commuters in Minnesota he gets from home (near Lake Nokomis) to work (at Westminster Presbyterian Church in downtown Minneapolis) in a gas-powered vehicle, and uses the same car to make daily rounds visiting church members at homes, hospitals, apartment buildings or elsewhere.

But after an offer from a bike company, for one day recently Shinn carried out his daily duties with a form of transportation that has taken Asia by storm, become one of the few bright spots in an otherwise flat U.S. bicycle market, and has generated both envious and dubious reactions from bicycle purists.

Shinn — and much of Minnesota — meet the electric bike.

E-bikes were not available from some major bicycle manufacturers until just this year. Their arrival has been aided by a nationwide push from the bicycling industry to change laws and influence lawmakers, some of whom regard e-bikes as motorcycles not suitable for bike paths. The arrival of more e-bikes on local bike routes and paths, meanwhile, has some bicycle purists pushing back against the unwelcome intruder.

Elsewhere, they've become something more mainstream. Nearly all electric bikes made last year were sold in Asia, with customers there taking 95 percent of the market, or about 30 million units. Imports of e-bikes into France, Germany, Spain, the Netherlands and Italy grew by about 50 percent between 2014 and 2015, according to Bike Europe magazine.

E-bike sales are expected to hit 35 million units this year, with 152,000 of those coming in North America, according to Navigant Research, a market research firm. Navigant predicted e-bikes sales to grow from $15.7 billion this year to $24.3 billion by 2025.

They still are a tiny portion of the overall bike market in the United States, and for many riders, such as Shinn, e-bikes are a wholly new ride.

"It's a fascinating experience," said Shinn, a fit guy in his 40s who runs the occasional marathon. "I think if you're someone who's biking for exercise, this would not be the bike for you; if you're somebody who's maybe a little older, biking for leisure, this is a very good leisure bike. I also think that biking downtown, with all of the stop and go, this is an easy bike to bike."

Pedaling the electric bike, Shinn slipped through Minneapolis traffic during his test ride wearing khakis, and a long shirt and tie on a hot summer day. Electric bike makers like to stress that their product allows people to dress for the destination, and skip the spandex, since they won't need to work hard if they don't want to.

His electric bike was built by Faraday Bicycles, a San Francisco-based manufacturer that won an Editor's Choice award this year from Bicycling Magazine. Known for stylish e-bikes with batteries concealed in the frame, Faraday makes an all-the-bells-and-whistles version that retails for $3,500. A less fancy version sells for $2,500.

Shinn said he was impressed with the bike, not only for the burst of power that helped get him rolling from a dead stop, but also for the way the motor synced with his own efforts.

"It was pure delight," Shinn said of the assisted ride. "I really appreciated the beauty of the bike and the technology behind it."

The bike was a loaner from local bike shop Perennial Cycle in Uptown, which carries the Faraday and other e-bikes. Riding the snazzy Faraday, Shinn said he won the envy of his co-workers when he wheeled it into his office.

"Everyone took turns to come in and look at it," he said.

Purists have noticed

The growth of the local e-bike market has caught the attention of conventional bicyclists — and not always for the best. Some in the mountain bike community, in particular, have had concerns about the use of e-mountain bikes, said Matt Moore, vice chairman of the Minnesota Off-Road Cyclists, a nonprofit volunteer organization that promotes the sport and helps build and maintain trails.

"You should go as fast on a mountain bike as you are capable of operating it safely," said Moore, who works as the general counsel for Quality Bicycle Products in his day job.

The state Department of Natural Resources doesn't allow the use of e-bikes on its nonmotorized trails if the electric motor can push the rider faster than 20 miles an hour. Moore said the jury's still out on whether or not higher-powered electric versions could damage trails. And, he asked, what happens to an e-mountain biker who rides into the mountains for 20 miles before running out of battery life?

The majority of e-bike sales are in commuter style bikes, such as the one that Pastor Shinn rode, and in that category, the e-bike has had much less resistance from traditionalists, Moore said.

Dorian Grilley, executive director of the Bicycle Alliance of Minnesota, said he is a fan of electric bikes but doesn't want to see them on a bike trail if they're capable of going faster than 20 mph.

Some Bicycle Alliance board members use electric bikes, said Grilley, and he thinks it makes perfect sense to use an electric bike as cargo bikes for "hauling kids around and things like that." He predicts more sales as bike riders age.

Grilley wants to see adequate education so that "people know that if they're buying a bike that can go 30 miles an hour that it technically is not permitted on a trail. I think that should be an obligation of a bike shop or a dealer."

As far as pushback against e-bikes, Grilley said he's heard from both sides of the debate.

"I think I've heard more of an understanding that these electric-assisted bicycles have a place but need to be managed and monitored to ensure safety. There are certainly some purists out there who don't think they should be on the Greenway, but I think they're in the minority."

Some state laws still regard electric bikes as a motorcycle, and that creates problems for bicyclists because most departments of motor vehicles wouldn't issue a license for an e-bike, said Morgan Lommele, e-bike campaign manager for People for Bikes, the Boulder, Colo.,-based advocacy arm of the Bicycle Products Suppliers Association.

"We're trying to clean that up," she said of the laws that regard e-bikes as ­motorcycles.

What's legal?

In Minnesota, e-bikes were considered motorized vehicles until 2012, when state law classified them as a subset of conventional bicycles. The state law now says an electric bike must have a seat and operable pedals, two or three wheels, an electric motor of up to 1,000 watts, and that the motor must disengage during braking and have a maximum speed of 20 mph whether assisted by human power or not. The law sets a minimum operator age of 15.

An e-bike that doesn't meet these requirements probably isn't illegal, said Moore, but could be considered a motorcycle with different requirements.

Then there's the federal definition: The federal Consumer Product Safety Commission says an e-bike is a vehicle with two or three wheels, working pedals, a motor of less than 750 watts and a top speed of 20 mph without pedaling.

The combination of the two laws creates some confusion.

The state law says the e-bike must meet the federal regulations, so, for example, because the federal regulation says e-bike motors can't be larger than 750 watts, a 1,000-watt bike wouldn't be considered an e-bike in Minnesota, even though state law seems to say otherwise.

At the same time, a Class 3 "pedalec" bicycle with a 750-watt motor that can go 28 mph when the motor is engaged and the rider is pedaling would be legal to sell, according to the Consumer Product Safety Commission, but because the motor is still engaged when the bike is going faster than 20 mph, it wouldn't be considered an e-bike in Minnesota.

"Sorry this is confusing," Moore wrote in an e-mail. "That is the way it is."

Sales growth

Driving the work of the bicycle industry to clarify the rules on e-bikes is the very real growth in their sales across the country. Though not on the scale of sales in Europe or China, U.S. retailers have seen tremendous growth in e-bike sales this year.

"I started doing this work about a year and a half ago, dedicated to policy work on e-bikes and at that point, many manufacturers were still very skeptical about the future of e-bikes," said Lommele. "But you look at the bikes coming through the 2017 season, all of the bike manufacturers are offering electric bikes," she said. The industry's only growth areas right now are in commuter bikes and electric bikes, she said.

Even more exciting for bicycle retailers is the sense that many of the people buying bikes are new riders.

Clint Stockwell, the founder of the Minneapolis Electric Bicycle Company, said he's sold out of his $1,700 e-bikes. A new shipment expected this fall will be available at Evolve Segway in St. Louis Park. As e-bikes sales grow, Stockwell said, they'll keep pushing changes into the ­transportation system.

"Can you imagine a whole lane for electric bikes down 35W?" he asked during an interview. "My friends, they can't imagine it. It's too much for them, but I can imagine it."