Shortly after the coronavirus pandemic shuttered indoor spin studios, Alex Haigh found herself craving cardio.

She tried running but kept injuring her ankles. It wasn't until a friend gifted her a 1980 Miyata One Hundred that she decided to take her love for indoor cycling outside. But before she could do that, her vintage tubes needed a tuneup.

"The hang-up for me was that the bike needed work, and it took about three weeks to get it tuned up at Bike Gallery," says Haigh, 32, who lives in the Buckman neighborhood. "Not sure how long it normally takes, but I assume that's a big delay."

She's not wrong. Across the country, bike shops and retailers face a historic shortage of stock, merchandise and basic repair items, all the while operating with a skeleton staff. The reason? COVID-19. The virus has slashed supply chains to a standstill but also increased demand tenfold as customers seek out alternatives for transportation, exercise and enjoyment.

According to the NPD Group, which tracks consumer habits, nationwide bike sales doubled during the month of April, and interest in affordable, adult leisure bikes shot up 203% compared with last year.

In Portland, where biking is already a prominent part of the culture, local shop owners and advocates see the bike boom as a chance to roll out the red carpet for new riders in the hope they will stick around.

"Every time there is a boom, you are going to capture a certain number of people," says Jonathan Maus, founder of the cycling blog BikePortland. "Biking gets under your skin, it makes you feel better about your body and your city. It just depends on how many people we can keep for the long term."

One of those new riders is Brandon Brezic.

"This is basically my first bike purchase as an adult," says Brezic, 25. "Being so isolated made me stir crazy, and I wanted an excuse to get out of my apartment. I think my partner probably wouldn't have been so quick, though, to buy had COVID not happened."

Brezic ordered his Retrospec Mantra-7 hybrid during quarantine in April and received it a week later, assembled and ready to go. But for his partner, Mackenzie Verrey, the model she had her eye on—SixThreeZero's Reach Your Destination hybrid—was back-ordered until late August.

That kind of delay is common not only across the country but globally, according to Cassandra Hidalgo, owner of Gladys Bikes on Northeast Alberta Street. Her shop can hardly hold any stock without selling out within the week, while her suppliers in China and Taiwan are playing catch-up.

"It's been really surprising," she says. "People have been eager to wait two weeks for an appointment, and to buy without seeing the bikes right away."

The same can be said for even Portland's larger retailers, like River City Bikes, whose showrooms have been closed since March and bike sales take place in the parking lot.

"We just can't keep hardly anything in stock, and when it comes in stock, it is immediately gone," says Ryan Barrett, River City's marketing and e-commerce manager. "But another layer is, this isn't a local pandemic, it is a global pandemic. Our supply chains were shut down in Asia, and it made it difficult to stock our shelves."

This isn't the first time a public crisis has made people turn to bikes in droves, according to Michael Andersen, a senior researcher at the policy think tank Sightline Institute. In the 1940s, an oil shortage led lawmakers in the Netherlands to move away from automobiles and form policy geared toward greener transportation. In the 1970s, Portland invested in the environment after yet another oil shortage, and with that came the city's first Bicycle Master Plan.

So it's no surprise to Andersen that people have turned to bikes during this pandemic, when public transportation ridership is down, businesses are closed and commuting is reduced.

"There is now a chance that more people have been exposed, a percentage of people are going to love it and see it is useful," says Andersen. "Hopefully that will be the basis of another round of enthusiasm for this form of transportation."

Out on the greenways, the enthusiasm is hard to miss.

"The type of people I've seen out is different. It seems like the Sunday Parkways phenomenon," Maus says. "The number of families out right now is unbelievable, the amount of people riding with young kids is amazing. That is something you wouldn't see that often on a daily basis."

But short-term successes like swelled bike lanes and sold-out inventory are not what advocates are thinking about.

"There have been significant bike-shop closures in the last few years," Andersen says. "A big part of bike-shop economics isn't the selling of the bikes. They are mostly relying on the service relationship going forward."

Sustaining the momentum for bicycling also brings up the issue of safety. Even with heavy investment in initiatives like Portland's Vision Zero, which aims to eliminate traffic deaths, the city saw fatalities rise nearly 20 percent in some counties in 2018.

"Portland is kind of a bubble and a poster child for bike transportation, even though there are still unsafe places and there are still people that die," Hidalgo says. "I think what this is going to do is cause more safety and awareness and, hopefully, a lot more bike infrastructure."

Maus believes new riders will only stay on the streets if they feel safe, and protected bike lanes is the way to do it.

"I don't think we have taken full advantage of the moment in terms of making biking safer than the way we could have," says Maus. "You can't just put up lines and think that you've done enough."

For some, however, the thrill of freedom after months of lockdown may be just enough to get them to stick.

"After getting my own bike, I finally realized why Portland is such a big biking city," Brezic says. "Maybe one day I'd like to even ditch my car altogether and jump on the E-bike bandwagon."