Adrian Braun, a master of custom BMW boxers, has crafted a stunning scrambler based on an R90/6. Operating out of Melbourne, Australia, under the moniker Skrunkwerks, Braun’s deep understanding of Bavarian airheads shines through in this meticulously built machine.
The bike’s transformation began with a complete teardown, revealing a boxer twin engine that was ripe for an overhaul.
A Siebenrock big bore kit pushed the displacement to 1,000cc, while ported cylinder heads, a higher compression ratio, and a new camshaft bolstered performance. Dellorto PHM carburetors, breathing through K&N pod filters, and a Danmoto stainless steel exhaust system further enhanced power delivery.
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Braun’s ingenuity was evident in the custom carbon fiber cover that replaced the OEM airbox, and the upgraded 1987 R 100 gearbox. The bike’s versatility was ensured by a new subframe with an integrated rear luggage rack and mounting points for SW Motech saddlebags, making it ready for both urban adventures and long distance touring.
The R90/6 scrambler is a testament to custom craftsmanship. Perforated side covers adorned with Skrunkwerks badges flank the subframe, while a solo seat sits atop. Dual-function LEDs are mounted on the frame tubing, flanking a wooden encasement made of Tasmanian Tiger Myrtle.
The same material was used to create custom knee pads for the original R90/6 gas tank. Bespoke fenders were installed front and rear, and the wheels were fitted with stainless-steel spokes and dual-purpose Heidenau K 60 tires. The stock forks were retained and refurbished, but the rear shocks were replaced with modern, slightly longer Ikon units.
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A Suzuki GSX-R750 four piston Brembo caliper and a floating aftermarket disc originally designed for the Ducati 1198 provide additional front end stopping power. A Magura radial master cylinder controls the brakes, and a Renthal handlebar with Kellermann bar end turn signals completes the cockpit.
A compact Daytona dial, wired through a Motogadget control unit, manages the electronics. The scrambler’s monochromatic color scheme is accented by vibrant orange paint on the fuel tank.