LAUDERDALE, Minn. – With callused hands and a face lit by grinding wheel sparks, Jack Carlson toils for hours in his garage.

He is driven by a simple notion. Jack believes every kid should ride a bike.

“If I had a dollar for every time I’ve heard a parent say, ‘I never thought they’d be able to do this,’ I’d definitely be a lot richer now,” he says.

Given that dollar, Jack would probably give it back. It’s not money that drives him, but putting kids with physical challenges in the rider’s seat.

Jack Carlson measuring the seat height on a bike he rebuilt 

“There’s always a way,” he says. “There’s always a way.”

Word-of-mouth can travel faster than a 10-speed Schwinn, and Jack is becoming known in the therapy community as a go-to guy.

Sometimes he’s able to make minor modifications to existing products. Other times Jack pulls out his grinding wheels and welder and goes to work MacGyver-style.

Madison Rippy (left) and her sister Sidney both ride bikes from Jack Carlson. The girls are pictured with their parents, Linsey and Noel Rippy.  

“I cried, because I didn’t know if I’d ever see my kids ride a bike,” Linsey Rippy says.

Both her daughters, 11-year-old Madison and 8-year-old Sidney, are heart transplant recipients. Both ride three-wheeled bikes set up by Jack.

Jack put 7-year-old Lila Tjader on a bike too, despite her cerebral palsy.

Lila’s mother, Aimee Jordan, says the bike has given Lila independence. Aimee points to a cul-de-sac up the street from the family’s Plymouth home. “She gets to show off over there while all the kids are outside, riding her bike and not her wheelchair,” Aimee says.

Lila Tjader with her little brother Ridley Jordan 

It’s the kind of freedom Bobbie Jo and Adam McDermott want for their daughter, too.

“I looked in toy stores, online, everywhere,” says Bobbie Jo, whose 3-year-old daughter Carlee has a form of dwarfism, leaving her legs too short for regular bikes and riding toys.

For Carlee, Jack cut up - and then welded back together - a pink princess bike, the smallest one he could find.

Jack Carlson presents Carlee McDermott with her bike, as her mother Bobbie Jo looks on

“The best part of doing all this stuff is seeing the kids smile when you’re done,” he says.

Jack, too, is a perfect fit - for this work.

He started part-time in a bike shop as a teenager and still works with bikes four decades later, currently at Strauss Skates & Bicycles in Maplewood.

Jack Carlson cuts down a princess bike 

“It was almost getting me to the point where I wanted to get out of it, I was tired of the same old thing,” Jack says. “And then this came along and kind of restarted the spark.”

Katie Welch sees a spark too - in her daughter - each time 7-year-old Layla hoists herself up on the seat of her Jack-built bike.

“It’s really the ability for her to be a kid, for her to have freedom and for her to go fast,” says Katie, who looked at hundreds of bikes for Layla that didn’t work, before she found Jack.

“They said it wasn’t possible and here he was picking up all these different parts and putting it together in this puzzle,” Layla's mother says.

7-year-old Layla Welcon on her bike rebuilt by Jack Carlson

Smiling broadly, Layla peddles her pink bike up the sidewalk away from her home. “I do adventures,” she says. “I get to fit in with other people.”

Jack would approve.

The smoke from his welder wafts through the garage, the molten metal on the princess bike still glows red.

“This is the best thing I do,” Jack says.

NOTE: Jack Carlson tries to keep bikes affordable for the families he serves. A page has been established to collect donations that help him defray costs.