To win the world’s longest non

Adam Burns and John Sonderman are wrestling with a giant plastic bag.

Inside Burns’ workshop in Pleasant Hill, they wrap the bag around a dark, elongated shape. The crinkling drowns out the sound of Boston’s “More Than A Feeling,” playing from a speaker hung above a workbench.

They will eventually suck the air out of the bag, squeezing together a mix of resin, Kevlar and carbon fiber around a fiberglass mold.

”It is very rare to find a boat made outta wood now,” Burns says. “So everything's a composite. It's just so much lighter.”

Burns displays a frayed piece of black and gray fabric with a shiny, sharkstooth-like woven pattern.

“So this is what we start with — just sheets of carbon,” Burns says. “Sheets of Kevlar, which, you know, again, you could stitch yourself a shirt out of. And then we're gonna turn those things into a boat.”

Although the frame is only 13 inches wide, the soon-to-be boat stretches 23 feet down the middle of Burns’ workshop. It’s so long that Burns had to cut a hole in one wall to accommodate it, intruding on his two-car garage.

This boat is destined for a client with a specific purpose in mind: the Missouri River 340 (MR340), billed as the longest, non-stop river race in the world.

Beginning on August 1 at Kaw Point Park, hundreds of paddlers will begin a 340 mile-journey from Kansas City to St. Charles, Missouri.

“These boats have been designed and redesigned so that they're not ocean-going boats,” Burns says. “They're not meant to take huge waves, swells — so rivers, lakes, you know, big bodies of water that are not the ocean.”

Burns has a lot of experience in boats like this. As part owner of River Hawk Boat Shop in Lee’s Summit, Burns and his partner Joe Mann are one of the few custom racing boat builders in the country.

River Hawk has an enviable success record: For the past eight years, each of the solo winners of the MR340 has done so in a River Hawk boat.

Burns and Mann have only owned the business since 2021, after buying it from the previous owner. But both are seasoned racers, and MR340 champions.

Mann had raced in the Texas Water Safari in the past. It’s a shorter race, at 260 miles, but it runs on the narrow Guadalupe River, full of tight turns, debris, small waterfalls and dams that racers have to navigate.

Mann says the Texas Water Safari, which calls itself the "the world's toughest canoe race," is like mountain bike racing. But on the smooth and wide Missouri River, the MR340 is more like a road bike race.

“You could conceivably get in the boat at the beginning of the MR340 and never have to get out,” Mann says. “And you're not gonna go over any dams or waterfalls or rocks or portages.”

Even so, the MR340 is a real marathon: It can take 40 hours to complete for the faster boats, while others finish in twice that amount of time.

Mann and Burns became friends while racing in the MR340 in 2007. For each, it was their first year in the race and the start of a friendship.

“We ended up paddling next to each other with a couple of other guys for a pretty decent portion of the second day,” Mann says. “And we kind of got along and hung out on the water and, you know, had a good time.”

They ended up racing together in 2021, with a boat they designed themselves, finished as the overall winners (completion time: 35 hours, 42 minutes, 14 seconds).

They arrived at the finish line in the “Kraken” — an unusual, multi-person boat that’s paddled using recumbent bicycles.

Adam Burns plugs a hose into the plastic bag, now fully encasing the epoxied boat, and sucks the last drops of air out of it.

It generally takes a day for epoxy to be squeezed out, then a few more days of curing before they add another layer of epoxy.

There’s not much to do at this point except for Burns and Sonderman to sip some coffee and knock off for the day. For both of them, this is only a side gig.

“We're teachers,” Sonderman says. “I'm a counselor. He (Burns) was a fourth grade teacher. We started on the same day in 2004 at (Grandview C4 School District), and we've been there ever since.”

Like a lot of teachers, they looked for something to do in the summer to keep a little cash in their pockets.

“So we started painting houses, doing minor construction for people and whatever — helping people and mostly all friends and family stuff,” Sonderman says.

Sonderman even helped Burns build his home, which stands about 20 feet away from the combined garage and workshop.

“But we did that for a long time,” Sonderman says. “And then he was like, ‘Well, I'm buying a boat business.’ I go, ‘All right, I can help you with that, you know, if you want it.’”

Two years ago, Burns and Mann snatched up the opportunity to buy River Hawk Boats and began building boats as fast as they could — ones that could speed down the Missouri as fast as possible. They produce around eight a year, and a basic one-person model starts at $5,400.

This is Sonderman’s first summer building the boats, although he doesn’t race himself.

“Joe and I just looked at it as an opportunity to kind of take it and move it to a different place,” Burns says. “And so I think since we've had it, we've had it about a year and a half. I think we've built 14 boats in that year and a half. So we've built quite a few boats.”

With such a niche purpose, it’s not a business that will make them rich. The men say boat-building is more like therapy.

“Working in a school is tough and to, you know, to have these couple months to just, you know, work at your own pace, work on something that you like, and to have a tangible product that you can see at the end of the day is really cool,” Sonderman says.

“You don't really get that a lot of times when you're working with kids,” he adds. “It's obviously really rewarding. But this gives you that little mental break and you're more ready to get after it in the fall at school.”

Burns and Mann will both be in the water this week for the MR340, although competing against each other.

Mann is building a boat based on the same structure of this one, which he’ll paddle as part of a team of four.

Burns will be riding in a tandem boat he built with his 14-year-old son, Gus. The two of them have competed in shorter races together, and this is their first time doing the MR340 as a father-son duo.

“We've done really well in a few races, you know, competing against other grown men, groups of grown men and done really well,” Burns says. “I want to do well in the 340, but I think as a 14-year-old, he doesn't really understand what it means to exercise for 40 straight hours without sleep.”

Gus says he’s looking forward to the challenge, but he’s also hesitant about the physical demand. Although his dad is an MR340 champion, the longest race Gus has completed is 63 miles.

“I think it's gonna be a good experience,” Gus says. “I’m excited and I'm also dreading it.”

Either way, Burns says it’ll be a bonding experience to remember.

“You're only five feet apart,” Burns says. “So that's been one of the best things about doing it, is just to get to spend time with a kid who's 14 and when at an age where they're typically pulling away from you, you’re kind of able to keep a little bit closer.”