In this edition of Flashback Friday, we’re revisiting ten machines that proved craftsmanship isn’t just about turning wrenches, it’s about re-engineering the impossible. Whether it was a S&S café racer or a bolt-on kit that saved the BMW R18’s reputation, these are the builds that made us stop scrolling and start dreaming. Here are The Top 10 Custom Motorcycles of July 2023.
1. Unik Edition Benelli 900 Sei
If you’ve never heard a six-cylinder motorcycle at full tilt, you’re missing out on a mechanical symphony. Lisbon’s Unik Edition took a rare 1979 Benelli 900 Sei, one of only 2,000 produced, and transformed it into ‘Sinfonia.’ The goal was to create a six-exhaust masterpiece that was actually easy to ride, bridging the gap between vintage excess and modern handling.
The transformation is radical, centered around a single-sided swingarm swap from a Ducati Monster S4R. This required a complete redesign of the rear end to accommodate a mono-shock setup and a beefy 190-section rear tire. Up front, inverted sportbike forks and Kineo wire-spoke wheels complete a rolling chassis that looks as fast as it sounds.
The bodywork is a 3D-designed carbon fiber monocoque that flows from the tank to the tail. Underneath, aluminum fuel and oil tanks were fabricated to accommodate a Motogadget-based electronics suite. Finished in white and green with gold pinstripes and a six-into-six stainless steel exhaust, it is a staggering tribute to the first production six-cylinder .
The transformation is radical, centered around a single-sided swingarm swap from a Ducati Monster S4R. This required a complete redesign of the rear end to accommodate a mono-shock setup and a beefy 190-section rear tire. Up front, inverted sportbike forks and Kineo wire-spoke wheels complete a rolling chassis that looks as fast as it sounds.
The bodywork is a 3D-designed carbon fiber monocoque that flows from the tank to the tail. Underneath, aluminum fuel and oil tanks were fabricated to accommodate a Motogadget-based electronics suite. Finished in white and green with gold pinstripes and a six-into-six stainless steel exhaust, it is a staggering tribute to the first production six-cylinder engine.
2. Kingston Custom BMW R18 ‘The Crown’
Dirk Oehlerking of Kingston Custom has a knack for making the BMW R18 look like a relic from a high-speed future. To celebrate BMW Motorrad’s 100th anniversary, he created ‘The Crown,’ a machine that leans heavily into art deco and aeronautical design. Dirk’s process remains refreshingly analog; he stripped the R18 and sculpted the body using foam and cardboard before hand-forming the final fuselage from 2 mm aluminum.
The bike features a unique cable-operated steering system and a custom front swingarm to accommodate the dramatic, low-slung bodywork. The silhouette is massive, yet the bike actually weighs 40 kg (88 lbs) less than the stock cruiser. Dirk cleverly repurposed the R18’s LED headlight, reverse gear lever, and speedo, integrating them into a design that feels entirely cohesive.
The livery is the definition of class, utilizing champagne and mother-of-pearl tones that play off raw aluminum and chrome. With its slash-cut exhausts and pinstriped panels that recall vintage BMW tanks, The Crown is a regal reinterpretation of the boxer platform that defies conventional motorcycle architecture.
3. Sutton & Marsden S&S Cycle Café Racer
Andrew Marsden and Pete Sutton of Bristol, England, spent years testing the limits of what a home-built special could be. Inspired by the Manx Norton and the Isle of Man, they built a bespoke frame around a massive 1,600 cc S&S V-twin. The frame geometry was modeled after a Ducati 916, resulting in a heavyweight American engine inside a nimble, British-styled chassis.
The engineering hurdles were significant, particularly preventing the primary belt from jumping under the massive torque of the S&S engine. Pete Sutton fabricated a custom system to maintain optimum tension regardless of temperature. The bikes feature Ducati 916 single-sided swingarms and magnesium Marchesini wheels, creating a high-spec racer aesthetic that stands in stark contrast to the traditional cruiser engines.
While the prototype (V1.0) features a lived-in, race-ready look, the V2.0 build serves as a template for a limited run of made-to-order machines. With Manx-style alloy tanks and K-Tech internals, these builds are a testament to what happens when short-circuit racing experience meets obsessive fabrication.
4. Seb Hipperson’s Yamaha R9 Custom Concept
While the world waited for Yamaha to put its CP3 engine into a sportbike chassis, London fabricator Seb Hipperson got tired of waiting and built his own. His R9 concept uses the 889 cc triple from an MT-09 but ditches the plastic street-bike vibe for a chassis inspired by 90s GP two-strokes and modern Moto2 bikes.
Seb TIG-welded a custom steel trellis frame, utilizing the cradle from a Yamaha TRX850. He then added a Ducati 749 swingarm and Panigale forks upgraded with Bitubo internals. The bodywork was hand-shaped from fiberglass, featuring a muscle-car-inspired airbox vent that actually directs air into the intake to maximize the triple’s 110+ hp output.
The finish is a nod to Yamaha’s legendary speedblock racing heritage. With a raw aluminum fuel reservoir and a track-focused setup, including a thumb brake and a GPS speedo, Seb’s prototype is the R9 that Yamaha should have put into production years ago.
5. Purpose Built Moto Ducati GT1000
The Ducati SportClassic GT1000 is often seen as the practical sibling in the family, but Tom Gilroy of Purpose Built Moto turned it into a high-performance café racer. The key requests were an under-tail exhaust and upgraded handling. PBM delivered by fitting Öhlins suspension from a Monster 1200R and ultra-light Jonich M9 carbon-wrapped wheels.
The fabrication work is the star here. Tom designed a two-into-one-into-two exhaust system that passes through the swingarm and exits via two mufflers tucked under a bespoke sheet-metal tail cowl. The cowl was designed to mirror the tank’s lines, including the specific knee indents, resulting in a silhouette that is much tighter and more aggressive than the original.
A sharp chin spoiler was added to hide the fuel pump and provide access to the battery, while the front end was cleaned up with a PBM LED headlight. The black-and-yellow livery, executed by PopBang Classics, gives the bike a modern edge that perfectly matches its significantly improved power-to-weight ratio.