In the world of custom motorcycles, some of the finest craftsmanship comes from builders working quietly away from the spotlight. Marek Kruszynski is one of those builders you might not have heard of yet, but the custom scene is undeniably richer for his presence. Originally hailing from Poland, Marek now calls Brooklyn, New York home, where he balances family life with his wife and two kids alongside an uncompromising passion for classic machinery. By day, he works as a plumber, but when the sun goes down, his building’s basement transforms into the workshop of Marekswerk.
We first crossed paths with Marek at the second annual Builder’s Best Show during the BMW Motorcycle Owners of America National Rally in Essex, Vermont in June of 2026, and it immediately became clear that his engineering approach was something special.
Marekswerk operates on a two-prong philosophy: executing full ground-up custom builds while simultaneously engineering custom performance parts. Focused primarily on classic BMW R-series airheads and K-series, Marek doesn’t just build bikes; he manufactures solutions. His catalog includes custom rearsets designed specifically for the K-series chassis and adjustable paralever torque arms tailored for the K1100, filling mechanical voids in the aftermarket with factory-level precision.
Marek’s journey into custom motorcycle design is anchored in decades of deep mechanical involvement. Fascinated by engines from an early age, he taught himself the fundamentals of motorcycle mechanics through hands-on trial, observation, and endless hours of workshop experimentation. That early curiosity eventually led to a two-decade detour into the world of BMW automobiles, where he spent over twenty years mastering the brand’s complex engineering principles and diagnostic nuances. During that time, Marek became a fixture on enthusiast forums, helping owners solve tricky mechanical puzzles and earning a reputation as a trusted technical authority. When he ultimately returned to his two-wheeled roots, he brought that wealth of automotive knowledge with him. Today, his ethos centers on rescuing neglected airheads, combining timeless vintage aesthetics with contemporary CNC-machined components, modern electronics, and obsessive attention to detail.
To understand the legitimacy of Marek’s craft, one only needs to look at his BMW R100 Cafe Racer. The build immediately commands attention with its revised posture, starting with a WalzWerk rear subframe that visually lightens the classic airhead tail section. Perched atop the subframe is a custom tuck-and-roll leather saddle featuring an integrated faux cafe racer cowl, establishing the long, aggressive lines quintessential to the classic cafe racer silhouette.
At the heart of the build sits the iconic 980cc air-cooled boxer twin motor. While the stock engine originally produced between 60 and 70 horsepower, Marek refreshed the powertrain with completely rebuilt carburetors breathing through high-flow pod filters. The engine exhales through a custom-fabricated stainless steel exhaust system equipped with matching stainless mufflers, ensuring the 5-speed transmission delivers lively, crisp power with an intoxicating exhaust note to match.
Up front, the stance is modern and commanding. Marek binned the soft OEM telescopic forks in favor of a modern inverted front end, held securely in place by a set of billet Jax Garage triple trees. Clamped to the stanchions are low-slung clip-on handlebars that push the rider into an aggressive, tucked position. Custom rearsets move the foot controls back, reinforcing the bike’s purposeful racing posture. The cockpit is extraordinarily tidy: a Motogadget digital speedometer is flush-mounted directly into the top triple clamp, complemented by Motogadget push-buttons and bar-end turn signals for a clutter-free view over the controls.
Visually, the tank serves as the anchor for the entire composition. Marek kept the classic BMW R100 fuel tank profile but finished it in Isle of Man Green. This celebrated contemporary BMW automotive shade pays homage to the legendary Isle of Man TT road races. Grounding the build are BMW Y-spoke wheels, freshly powder-coated in satin black and wrapped in vintage-profile Shinko tires. Stopping power is handled by dual Brembo calipers up front, delivering modern bite to balance the nostalgic rear drum brake.
This R100 is just a preview of what Marek can deliver. As part of our Road to Barber series, we are excited to announce that Marek will be showcasing his work at the upcoming Builder’s Best Show Presented by BMW MOA at BMW Motorrad Days within the Barber Vintage Festival in Birmingham, Alabama, from October 9–11, 2026.
Marek is currently locked in his Brooklyn workshop, feverishly putting the finishing touches on an all-new custom build set to make its global debut at the event. With an estimated 85,000 motorcycle enthusiasts expected to gather at Barber Motorsports Park, it’s the ultimate stage for his craft.
If you’re a BMW enthusiast heading to the festival, you won’t just be a spectator; all BMW owners are invited to bring their motorcycles to the BMW Motorrad Days area on Friday and Saturday to park inside the show grounds and be part of the celebration.
Photo Credit: Greg Zastawny