Aeternum Blade custom Harley chopper unveiled by Rough Crafts

The Aeternum Blade, a fully reimagined 2024 Harley‑Davidson Street Bob, debuted with a 128 ci (2,097 cc) S&S big‑bore engine and a custom girder fork that blends CNC‑machined, 3D‑printed and hand‑crafted parts, marking a radical departure from the stock model [2].

Frame and geometry overhaul

Rough Crafts began by cutting the Street Bob’s stamped neck and square backbone, welding a tubular backbone, and raising the steering head 2.5 inches while moving it 0.5 inches forward, while retaining the original 30° rake. This creates a compact, forward‑leaning stance reminiscent of classic choppers yet remains maneuverable [2]. The bespoke girder fork, a skeletal assembly of CNC‑machined billet aluminum, 3D‑printed components and handcrafted elements, houses an Öhlins HD207 damper, reviving a pre‑1940s suspension design with modern performance [2].

Powertrain and component upgrades

The stock Milwaukee‑Eight engine was replaced with a 128 ci S&S Cycle big‑bore kit, boosting displacement to 2,097 cc. Instead of the factory electronic fuel injection, the build uses an S&S Super E carburetor fed through an Altmann conversion kit and a Rough Crafts‑branded air filter, restoring a raw, mechanical character [2]. Additional performance parts include a Baker hydraulic clutch housing, an open primary from Belt Drives Ltd., and a custom chain drive with an RK Takasago chain and a bespoke rear sprocket. The bike rides on 21‑inch front and 18‑inch rear Fatboy Design wheels shod with Metzeler Cruisetec tires, and features Beringer six‑piston front and four‑piston rear brakes with custom disc carriers [1].

Aesthetic and finishing touches

The chassis received a two‑tone powder‑coat finish that mimics a vintage lugged frame, while Rover Works Custom Paint applied a Nardo Grey livery accented by silver‑leaf graphics. The cockpit is dominated by direct‑mount Frisco‑style handlebars, Lowbrow Customs grips, and Rough Crafts‑branded pegs. A petite, scalloped‑sided fuel tank with a Rough Crafts filler cap sits above a bobbed saddle from Rich Phillips Seat Co., and the bike’s exhausts are hand‑finished Rough Crafts pieces. A small Motogadget speedometer floats between the massive cylinder heads, supported by a handmade bracket [1].

What to watch

• Upcoming showcase events where Rough Crafts may display the Aeternum Blade, potentially influencing demand for high‑end custom chopper components.
• Release of detailed performance figures (horsepower, torque) for the 128 ci S&S conversion, which could set new benchmarks for custom Harley builds.
• Any future collaborations between Rough Crafts and component makers (e.g., Öhlins, Beringer) that might introduce new aftermarket suspension solutions.

The Aeternum Blade demonstrates how a stripped‑down Harley platform can be transformed into a precision‑engineered chopper, blending classic aesthetics with cutting‑edge suspension technology, and raises questions about the future of bespoke motorcycle engineering in a market dominated by factory models.