Grandpa’s Bianchi becomes a stealth e-bike with a custom solenoid gauge hidden in the handlebars

A builder known as GRMNT has transformed a classic Bianchi road bike inherited from his grandfather into a sleek sleeper e-bike — a conversion that looks like a vintage bicycle but packs modern electric assist. The project preserves the original aesthetics while adding a fully functional electric drivetrain.

The frame is high-quality Tange steel, a mark of the Bianchi's premium build. After stripping years of accumulated grime, the builder installed a second-hand Bafang mid-drive motor, rebuilt for reliable performance. The motor is the core of the electric boost, but the most distinctive feature is the custom display.

Instead of a typical LCD screen, GRMNT built a solenoid-powered electromechanical gauge into the handlebars. The display shows battery charge level through physical moving elements, giving the bike a unique steampunk-inspired look that blends perfectly with the classic frame. The battery pack itself is hand-built and concealed inside a leather case, while the motor activation button is hidden from plain sight.

The result is a true sleeper: the bike does not scream "e-bike" at first glance. It looks like a traditional road bicycle, yet it provides electric assistance when needed. The project highlights how vintage bicycles can be upgraded with modern technology without sacrificing their original character or visual appeal. GRMNT's build joins a growing trend of custom e-bike conversions that prioritize stealth and style over obvious electric components.