From outside Mike Rust’s ramshackle compound tucked into the base of Copper Butte, you can just make out Great Sand Dunes National Park, 60 miles east across Colorado’s expansive San Luis Valley. The dunes form when southwest winds whip up sand on the valley floor that was left behind when ancient lakes receded. Here, a saddle in the Sangre de Cristo Mountains stalls the gusts, allowing the sands to accumulate. By the time I visit Rust’s place, northeast of the town of Saguache, the grit has worked its way in.

Jerry Mosier ties a bandana behind his neck, pulls it up over his mouth, and ducks inside. It’s 2010, and the place has been abandoned for a year now. Pack rats and field mice moved in quickly. In this climate, mouse droppings often carry Hantavirus—a disease that kills a few people in the state every year.

I tuck my nose into my shirt and follow Mosier inside the truck camper Rust built his house around; it was his bedroom. Here, the little kitchen where he’d grill cheese sandwiches, four to a square pan so as not to waste a breath of propane. In a corner, a museum of hand-built model airplanes. On a table, the brass roses Rust cut to sell for grocery money. The place is all grime and squalor and the odd angles of a home screwed together as needs and materials aligned. Rust refused to nail anything, opting to scab on new additions (the entire place is built from reclaimed materials) by hand-turning screws instead. Still, tucked into the hill and windowed to the south and east, the passive solar was so efficient that on the coldest days in January the shower released gushing hot water. He cooled his fridge on $5 worth of propane a year. His brother Marty told him that if everyone in America had his purchasing habits, the economy would collapse.

Mike Rust's house
Jamie Kripke

Mosier moves through the compound easily, remembering Rust’s home as he experienced it, seeing his friend in the quirky features. We eventually work our way into the shop Rust built. As one of the influential figures in the development of the modern mountain bike, Rust had lots of bikes and parts. Drivetrain parts on the second shelf. Hubs up top. Wheels out back.

Rust called the compound the Saguache Intergalactic Airport because it featured a runway—for landing his model planes and ultra-lights—that he painstakingly graded with hand tools.

After 14 years living on his 80 acres of high desert, Rust also paid lots of attention to tracks. Bear and cougar, coyote and mule deer. He could tell if a friend had driven in while he was out, or if a girlfriend or one of his many siblings had tried to pay a visit. Fifty-six years old, his short beard gone to gray, Rust had long settled into his rural, low-impact, off-the-grid life. He’d log the tracks into his journal along with meteor showers, passing jets, the births of rabbits, fledging bluebirds, and a bloom on a cactus, his mind making sense of the high-desert entropy the same way his helter-skelter home revealed its order in silos of focus.

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But the tracks Rust noticed as he drove into the long sand-and-dirt driveway to his home on March 31, 2009 never made it into his journal. Tire tracks (perhaps from dirt bikes, maybe a truck—investigators aren’t sure which). The trespassers hadn’t parked in front. They’d gone around to the west. Not visitors. Rust backed his car into the shed and carried his groceries into the house, setting them on the kitchen floor. His binoculars had been moved.

Mike Rust
Carl Rust
Rust had a passion for motorcycles and bicycles. His brother remembers him as

He recalled that while driving in, he’d seen tracks leaving the driveway about a third of a mile from the house. They headed north, which was unusual in that it was not the direct route back to the highway. He plugged in his cell phone—the only way it worked after he’d accidentally dropped it in water—to call his friend Mary Ann Bavaria, who lived over the pass in Salida. He told her he was going to track the thieves. His voice sounded frantic. It was exactly 7 p.m., darkness pooling in the valley.

Mary Ann went to sleep worrying. What happened next has fallen to Jerry Mosier to figure out, both as Rust’s best friend of 35 years and as a private investigator.

Mike Rust grew up in Colorado Springs, the fourth of eight children. As a military kid with the freedom to find his way in life, Rust took to motorcycles—as a teen, he secretly built one in his room, stashing the chassis under his bed—and bicycles. His brother Marty remembers him as “hell-bent on two wheels.” In the 1970s he also road raced in Colorado Springs. Five-foot-nine and 140 pounds with powerful legs, Rust was built for cycling. He had some success as a Cycling Federation racer. By the late ’70s he was converting vintage Motobecane touring bikes for the long, dirt-road climbs of the Rockies. These weren’t what you would think of as mountain bikes—Mosier called them “Mike-rigged” bikes—but they sparked Rust’s passion for dirt.

Jerry Mosier
Jamie Kripke
Jerry Mosier never imagined he’d be investigating the murder of his best friend.

In 1980, Rust, Mosier, and a dozen cyclists on various iterations of Mike-rigged bikes set out for an ambitious 400-mile-plus dirt-and-asphalt tour from the Springs over the Continental Divide to Crested Butte and beyond. “From Salida, we rode into the mountains on a dirt road we believed would get us over the Divide,” says Mosier. But the trail didn’t connect. “Everyone backtracked and rode over Old Monarch Pass,” says Mosier. “Except Mike. He made his own way over the Continental Divide, sliding down a scree slope somewhere near Crested Butte with his bike on his shoulder, a family of tourists snapping pictures as he descended. We called the crossing Rust Pass.”

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The rest of the party eventually caught up with Rust in Crested Butte and continued on without him to Paonia, where they ran out of cash and picked plums to earn food money for the ride home. Rust, enamored with the burgeoning countercultural fat-tire scene in Crested Butte, stuck around, wrenching in a shop owned by a man later wanted for cocaine smuggling. There’s a shot of 28-year-old Rust on the cover of the Crested Butte Chronicle dated September 1981. Wearing a full dark beard and dressed in a French team road-racing kit, he’s power-sliding a Trailmaster Klunker, one of the first production mountain bikes.

Mike Rust's Compound
Jaime Kripke
The details of Mike Rust's compound.

By 1986 he’d reconnected with he and Mosier’s mutual friend Don McClung, a second-generation machinist and gifted cyclist, and moved to the mountain town of Salida, where the pair opened Colorado Cyclery. They built bikes called shorties. The idea was simple: If they shortened the wheelbase, they could increase traction on the rear wheel and tighten the turning radius. To do it, they ditched the industry-standard double-diamond frame. Their prototype now hangs in the Mountain Bike Hall of Fame in Crested Butte. It was the first elevated-chainstay mountain bike. But the real breakthrough was the wheelbase—nearly three inches shorter than the norm.

Rust told a local reporter he was going to turn the old railroad village into a bike town in the style of Crested Butte. He pioneered and helped create and protect much of Salida’s local singletrack. A dedicated bike commuter, he’d ridden 200 miles round trip on a touring bike a few times to see his mother. He helped the leaders of the city of Colorado Springs with their bike-transportation planning. He fixed up bikes for kids and organized fun races in the city park. And he became an expert at riding a reproduction ordinary, one of those big-wheel bikes from the turn of the century—hand built, of course, in Colorado Cyclery.

Local mountain bikers on shorties competed in regional races. Younger riders expanded the trail networks he’d built. Free of the mainstream bike industry, Rust and McClung continued experimenting. In 1991 they put together an “enduro shortie” with a 26-inch wheel in the back and a 29er up front. It was likely the first 69er ever built. That same year, Rust was inducted into the Mountain Bike Hall of Fame. The honor came with a big house in town for the weekend. He invited everyone he knew and they partied through the night.

But along the way the once-sleepy community changed, and so did he. When the elevated-chainstay concept that he and McClung had developed was bastardized by cheap look-alikes, he felt betrayed by the bike industry. In town there were tourists around now, and he didn’t like to have to look first before crossing the street. In 1995, he and McClung closed Colorado Cyclery. Rust took his savings and purchased the property at the base of Copper Butte. The move put him closer to Mosier in Alamosa. But in Saguache County, he was still 50 miles, one mountain pass, and, in certain ways, a hundred years away.

Mike Rust's Compound
Jaime Kripke
Rust's compound sits untouched since the day he disappeared.

It was nearly dark on the night of March 31 when Rust began following the tracks. Stars would have been visible in the great bowl of the sky. To the south he might have been able to see the dim glow of town beyond the ridge. The closest neighbors were a half-mile away and up a neighboring drainage. And anyway, they weren’t particularly friendly.

Investigators later concluded that Rust left the house in a hurry. Meticulously frugal and perennially broke, he habitually reused coffee filters until they fell apart, so he had to have been hot to leave his perishables on the kitchen floor. What they don’t know is if he took his .22 pistol with him as security, or if the gun had been stolen and was in the hands of the intruders.

Mike Rust elevated bottom bracket
Jamie Kripke
Rust was a pioneer: He and McClung developed the first elevated-chainstay concept.
Mike Rust Police Bike
Jamie Kripke
Rust was a jokester: He used his mock police cruiser during a local festival to write pretty women citations for

It’s probable he saw the trespassers coming back shortly after ending the call with Mary Ann Bavaria. In the shed, Rust fired up Mosier’s Honda CRF 250, and in the process of exiting kicked over a gas can with the rear wheel. Then he sped off down his sandy driveway and onto the county road in pursuit.

It didn’t take Rust long to catch the trespassers. He bridged the gap about halfway to the highway. What happened next is only theory, but it’s likely that a heated Rust confronted the intruders. Maybe there was some shoving. Perhaps somebody pulled the .22.

When Mary Ann couldn’t get through to him by the next morning she drove over Poncha Pass to his house. Quite scared by what she found, she called his brother Paul who called his younger brother Marty. The two drove to the house that evening to help search. Mosier was away at the time, but he began making plans to come home and help. On the morning of April 2, they called the sheriff.

Don McClung
Jamie Kripke
Don McClung and Rust opened Colorado Cyclery together—and continued experimenting with bikes even after they closed its doors.

On Saturday, April 4, four days after Rust had gone missing, a search party discovered a bloodied vest. Nearby, the sheriff found spots of blood and discovered a wooden grip broken off a gun. DNA testing proved it was all Rust’s blood.

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Much that remains is conjecture: The men either had a truck, had one parked nearby, or quickly retrieved one. At that hour, they wouldn’t have much time. Rust’s distant neighbors could still be expected on the shared road. Aided by nightfall, the burglars got Mosier’s motorcycle and almost certainly Rust’s body into that truck, continued a quarter-mile down the dirt road, crossed paved Highway 285, opened a gate, and came to the intersection of County Road AA, another dirt road that runs due east to the Sangre de Cristos. That’s where search dogs lost the scent.

Jerry Mosier and I don’t stay long in the tight air of Rust’s compound.

We step back outside, drawing deeply of the fresh air under a sky so big you feel the earth curve. With an average elevation of 7,500 feet, the San Luis Valley (or El Valle, as Rust and Mosier called it) is the biggest alpine valley in the world—an inland sea of dust and brush the size of Connecticut. The Sangre de Cristos rise up out of the desert to 14,000 feet and roll down into northern New Mexico. The sky dominates the landscape; Saguache is a Ute word for Water at the Blue Earth.

“I never thought I’d be investigating the murder of my best friend. You make a decision when you’re eight that you want to be an investigator and live a romantic life, but there’s a moral obligation that comes with it. And here I am.”

But for all the sun, it’s a bleak place. Much of downtown Saguache is boarded up. A few miles south, you’ll see stark potato farms and cowboys on horseback moving cattle. Saguache is one of the poorest counties in Colorado. More than 2,000 of the 6,000 residents—many of whose families have lived in this barren country since the gold rush—exist below the poverty level. Eight lawmen and one investigator patrol an expanse inhabited by fewer than two people per square mile. A walk through the Saguache graveyard reveals shallow graves, not just of the long-deceased miners and migrants, but the recently departed poor as well. The newer graves are often marked only by a cross of wired rebar.

Rust called the area’s lowlifes and transients “sap-sucking drifty shitbirds.” He’d been in a scuffle or two. Mosier describes his friend as “Swiss-precise in his actions and Irish-blunt in his demeanor.” He tells of a time in a Saguache diner when he and Rust were listening to an angry redneck unmercifully berating his wife and kids. Rust walked over to the table and said: “Mister, you have a lot of class, but unfortunately it’s all low class.”

Mosier is a retired private criminal-defense investigator. Or at least he was supposed to retire. Now he finds himself investigating the disappearance of a man who, when mountain biking was young, used to take Mosier on epic rides that usually ended with the pair getting lost in the mountains. Mosier stored his motorcycle in Rust’s garage. Rust built bikes for Mosier’s kids. From his front stoop, Rust would mirror the sun’s light 50 miles across the valley to Mosier’s place in Alamosa. Mosier learned to mirror back. Rust called him Inspector.

Before he vanished, Rust still rode everywhere and cobbled together bikes for friends, nieces, and cute waitresses. On summer weekends the compound would be abuzz with kids running around and the sound of throaty dirt bikes or whirring model planes. Mosier was always stopping by, as was Bavaria and Wade Veazy, the owner of Salida’s SubCulture Cyclery mountain bike shop and an old friend and disciple who shared Mike’s worldview. In winter, the road could get snowed in for weeks and Rust would hermit away, contentedly cutting roses before sledding his bike down to the paved road and riding into town for supplies. As lean and fit at 56 as he was 30 years earlier, he once told Bavaria that he planned on living at the Intergalactic Airport until he was 140.

Officer from the Saguache Police Department
Jamie Kripke
The Saguache Sheriff's office used helicopters, planes, and a dog team to search for clues.

We load into Mosier’s truck for the drive back to town. As he talks, Mosier maintains a cool distance, trying to keep from saying too much as an investigator tied to the case. We park and he gazes over the dash, avoiding eye contact. “I come up to Saguache pretty frequently,” he says. “Try to make people nervous…. That’s an old gunfighter joke.” Then he turns and there’s a shine to his eyes. “At 72 years old, I didn’t think I would be investigating the murder of my best friend,” he says. “You make a decision when you’re eight that you want to be an investigator and live a romantic life, but there’s a moral obligation that comes with it. And here I am.”

Beginning the day Rust was reported missing and continuing through Monday, April 6, the Saguache Sheriff’s office coordinated search efforts that included two military Blackhawk helicopters, a C130, a private helicopter, one smaller fixed-wing craft, and a dog team out of Park County. The scene would have had Rust scribbling furiously in his logbook.

In the months after Rust’s disappearance, Mosier let it be known that if anyone had any information about the case, but didn’t want to deal directly with the sheriff’s office, they could come to him in confidence. A $25,000 reward was offered. As a grandfather himself, Mosier challenged local grandparents to voluntarily donate DNA for testing in the hopes they would get a familial match off some of the evidence. Nobody came forward.

“It’s easy to get away with crime here. There is also the character of today’s drug-driven criminals. They have time to murder and dispose of a body.”

If you pick up where the dogs lost the scent and turn left onto dirt road CR AA, you’ll drive 20-odd miles due east with the Sangre de Cristos filling your windshield. As you bounce along, you’ll pass a few rundown homes and half a dozen parched fields. Eventually you’ll climb into rugged piñon-and-juniper country. The road continues up after losing its name; snaking toward the Cotton Creek drainage. That’s where Mosier’s Honda was found a month after Rust disappeared, rolled down an embankment by someone who had a handle on the local topography. An accident-reconstruction expert from Colorado Highway Patrol confirmed that the bike had been placed there; nobody crashed it. It had snowed in April, but the moto was still bloodstained. Another 10 searchers scoured the area where the bike was found. But Saguache County is drilled with hundreds of unmapped mineshafts. It’s also home to hungry bear, coyote, and cougar. Despite the $25,000 reward—a lot of money in Saguache—more than four and a half years have passed without an arrest.

According to Colorado Bureau of Investigation (CBI) protocol, Rust’s apparent murder remains a missing-person case, which moves it down on CBI’s priority list. The Saguache Sheriff’s office, though, has treated Rust’s disappearance as a murder investigation since the discovery of the vest and .22 handle. The office spent $2,000 for the DNA test and asked that the case be moved up. Still, CBI didn’t finish its forensic study of the evidence until almost exactly two years to the day of Rust’s disappearance. If they found new evidence, the sheriff isn’t saying. In 2011, the chief investigator assigned to the Rust case moved away from Saguache.

As I sit with Mosier in his truck back at town, watching a few people come and go, I find myself disquieted. Talking with Mosier, I feel a sense of dread here that again belies the optimism of the relentlessly blue sky. The sheriff’s office I’d visited earlier felt silently besieged; a tension that comes with being outgunned and outnumbered and a long way from help.

There are currently three unsolved murders in Saguache County, including Rust’s. The first involves an unidentified gunshot body stuffed inside a plastic bag off a county road. In another incident, in September 2008, a smoldering barrel was found with the remains of a Saguache woman named Brenda Shepard inside.

I ask Mosier about the resident crime families, some of which date back a century. “If you confront them they will kill you and you will disappear,” he says. “Poverty breeds a poverty of spirit. The wide-open spaces, limited population, and the freedom that drew Mike and me to El Valle are also to blame. It’s easy to get away with crime here. There is also the character of today’s drug-driven criminals. They have the time to burglarize remote dwellings like Mike’s. They have the time to murder and dispose of a body.”

No cycling blogs blew up when Rust disappeared. The Mountain Bike Hall of Fame didn’t even bother to update Rust’s profile until more than two years after his disappearance—finally and officially noting that he was no longer living quietly in Saguache. It’s as if the emptiness, the void, somehow sucked Rust in, made him vanish, and we’re all helpless to do anything about it—a father of mountain biking, a brother, a son, a friend, now as ethereal as the fine dust that gradually buries the evidence of his existence.

“He was the best of what this country used to be about,” Mosier says. “On that original bike ride over the Continental Divide all those years ago, I gained a new appreciation for the old Western phrase, ‘We rode together.’ With horses or bicycles, there are some people you can ride with, but most you can’t. It’s nothing personal. I am proud to say I rode with Mike Rust.”

Update: On January 8, 2016, the Colorado Bureau of Investigation found human remains in Saguache County accompanied by Rust's bicycle-sprocket belt buckle; on April 25, 2016, CBI confirmed the remains were Rust's.