Reader Bike Check: A Mountain Bike Built for Building Trail

Eric Unger's Salsa Mukluk fat bike is built to haul a modified trailer full of heavy building tools and equipment.

I’ve always thought that it’d be silly to own one of those huge, dually, diesel pickups, with a crew cab, and mud flaps, but I’ve also never owned a ranch and would have a hard time towing a trailer full of horses with my V6. Most of us are in the same boat when it comes to trail building and want a bike that works best as a daily driver.

Volunteer builder and Overland Mountain Bike Association Trail Agent Eric Unger enjoys trail work so much though, that he’s built up a Salsa Mukluk that’s burly enough to tow out a heap of heavy tools to a dig site and comfortably handle a rocky trail at the same time.

“I wanted a fat bike to be able to ride all winter but also to do trail work with,” says Unger. “We work up the [Poudre] canyon throughout the entire season so having a rig that could handle snow, ice, and slippery tech sections was important.”

Unger went with a fat bike so he could throw on studded tires and because it can handle a BOB trailer more easily. The Mukluk has a 197mm-wide rear dropout and with a special axle from the Robert Axle project, he can attach the trailer, and tow in their grip of tools. Pictured above, that includes a 45 pound grip hoist and a 35 pound cable. Unger says his trailer can easily run around 100 pounds.

“It’s a lot of quad, core, and arm strength but it’s not bad. I wouldn’t want to do it on a non-fat bike. Once you get moving there is a serious amount of momentum working for you and you’ve got to compensate for stopping. It actually handles pretty good!”

He and Dave Kahl, a volunteers coordinator for OMBA, played with a few ideas on the BOB trailers, and found that extending the dropout on the trailer would work to get it fitted around the wider tires. “I’ve hiked that thing in before on foot and it was NOT fun.”

Like anyone looking for a bike in 2020, he had some challenges, but found one in October through Subculture Bikes in Salida, with a Shimano Deore build. Unger added a few upgrades for reliability and practicality. Since having boots rather than bike shoes is often necessary for a dig day, he used a wide set of Chromag Dagga pedals for a better footprint. That Dagga moniker is no joke. The pins put holes in the softer sole of another pair of boots he had before.

For instantaneous engagement while pedaling his cargo through the trail, he installed an Onyx rear hub with “infinite engagement.”

“This is crucial to me for getting through technical sections by ‘stutter stepping,’ because as soon as I press forward again on the pedals, I have forward power, which is the only way I’m going to make it through with all that weight.” The Onyx hubs work differently than a traditional ratcheting hub and instead use a Sprag clutch design.

Unger finds that trail work on the Mukluk helps him train for bikepacking, so towing the Griphoist and trail tools aren’t a fruitless labor.

A two-piston Hope stopper in the rear, and a 4-piston up front helps slow this thing down.

“It is a challenge and kind of training in a way for bikepacking where you have a 65-pound bike that you’re riding 35 miles in a day. Good trails take a lot of work to stay that way. I also like the artistic aspect of seeing a creek crossing, figuring out how to make it more user friendly for all trail users, and building the structure using trees from that area. I’ve been using and enjoying trails for so long that is is also nice to know that I’m giving back.”

In case you missed it, check out the story we did on OMBA’s Trail Agents program and read about the work that they’re doing.

Have a sweet or unique bike to show off? Tell us about it in an email: [email protected].