We have all heard The reliability of the classic BMW K-series is legendary, but the story of this BMW K100 street tracker is top notch. After all, how many motorcycles do you know that can spontaneously combust and still keep running?
The bike’s current owner, Duncan Bonar, found the bike in 1985. BMW K100 at a local shop with proper paperwork—but there was one catch. “The only catch is that it self-immolated from an electrical fire,” he explained. “But hey, a bike is a bike, and proper paperwork is still proper paperwork.”
Based in Los Angeles, California, Duncan is an industrial designer who enjoys tinkering with bikes in his spare time. During the day, he works as a designer at renowned off-road vehicle manufacturer, Meyers Manx. And before that, he was part of the team at boutique motorcycle brand, Arch Motorcycle.
Though Duncan has lined up a few project bikes under the Dunc Werks moniker in recent years, he began building the K100 a few years ago with less urgency, working as he had time. The K owes its brutalist aesthetic to Duncan’s background in industrial design and his tendency to figure things out as he went. “It was a do-it-yourself exercise with the resources at hand; a ‘often wrong but never in doubt’ kind of mentality,” he says.
Duncan’s first job was to get the K100 running again after its minor breakdown. “The wiring, electric fan and airbox assembly were all burnt. The engine and bike were pretty much caked in fire retardant, and there was a dent in the crankcase where the bike had fallen over at a traffic light when it decided to self-immolate.”
“Knowing that the K engine was relatively bulletproof, I wasn’t too worried about the internals. My bet paid off because there was no need to deal with the internals—I just had to reseal and refinish the engine.”
With the K100’s eight-valve engine growling again, Duncan could get to work on the rest of the bike. Embracing the K’s inherently awkward lines rather than trying to “smooth” them, Duncan retained the OEM fuel tank and fabricated an angular subframe with a curved rear hoop to face it. Next, he fabricated a myriad of aluminum parts to complete the bodywork.
“All the aluminum parts are designed by me using a clamp and CAD modeling software,” he told us. “The laser cutting is outsourced to a third party, and then the bending is done by me, using a manual bending machine.”
Custom parts include a seat pan, which integrates the bike’s electronics tray and battery mounts, and doubles as a rear fender. A row of LEDs sits at the back of the subframe, handling the taillight and turn signals when needed. At the opposite end of the bike, a license plate-style headlight houses a Baja Designs light and a small digital speedometer from Motogadget.
In the middle of the car, you’ll find a small custom panel designed to hide the coils. Duncan also embedded the ignition barrel in there, and later added a manual fuel pump switch when he realized that space was lacking something. “The extra switch flipping makes starting the car more fun,” he jokes.
Duncan stripped down the BMW wiring, tweaking it so he could use recycled Kawasaki switches. The cockpit has new Renthal handlebars; they’ve been shot-blasted and clear-anodized to give them a matte finish. The Motogadget speedometer is accompanied by a custom-made warning light panel.
Moving on to the K100’s drivetrain, Duncan rebuilt the stock forks with progressive springs and installed a new rear shock. The wheels and brakes are from a much newer BMW K1600, with custom axles, spacers, and caliper mounts to match. The four-into-one exhaust is from BSK Speedworks—a British racing shop that runs K100s in endurance racing.
Duncan’s specialty is colour and material design, so while the K100’s finishes are simple, they’re very intentional. “I was looking for something that was definitely classic, blurring the line between bold and understated,” he explains.
“Land Rover and their more expressive colours of the past have always been close to this mark. The resulting colour is a variation of Shetland Beige, a warm putty colour that complements Brick well.”
Duncan chose to paint only the tank, leaving the aluminum components raw to emphasize the concept of letting the manufacturing process guide the design. All the hard parts were given a fresh powder coat, leaving this rugged BMW K100 street monitoring looks much better than the charred remains it was originally.
Dunc Company | Instagram | Image by Duncan Bonar
