The Honda Super Cub is the most popular vehicle in the world with over 85 million of the little beasts being sold since it first hit the streets of Tokyo in 1958.

Now meet the the Firefly, the latest build by Deus Japan’s Director of Motorcycle Operations, Matthew Roberts – a venerable 1961 Honda Super Cub that pushes the engineering and styling envelope like none before.

Roberts says it's a modern interpretation of the raw functional beauty of small capacity GP and TT steeds of the 1950s and ’60s Its long, low lines, run uninterrupted from headlight to tail but for the riders perch – a spartan tuck-roll offering in Oxblood red, stitched by local moto upholstery master Miauchi-san, and the original C105 speedometer, a nod to the machine’s heritage. Its execution so harmonious as to have historians running to the archives in search of reference to a long lost racing prototype.

A modified frame and epoxy composite monocoque body of Roberts’ own design and construction, afford the Firefly its striking silhouette while saving precious kilograms. The inspiration drawn from the Cub's unique front suspension. The exceptionally slim top bridge and frame allowed the creation of a body 105mm at its widest point, while entry in local pre 1964 race series provided the performance motivation. As a neat twist, racing kit strips off quickly to reveal the machine’s road going necessities – headlight and discrete illumination elsewhere – meaning the Firefly can compete on the track at the foothills of Mount Fuji on a Sunday and hit the streets of Tokyo on a Monday.

Removing the body reveals fuel cell, battery, coil and electrics laid out with surgical precision along a slender modified back bone. Polished and trued original C105 hubs now sport made in Japan DID alloy rims, custom spokes and 2.75 x 17 rubber shoe-horned to fit inside the narrow forks and rear fender. Bespoke and hand-made accoutrements pepper the Firefly’s form, such as alloy top bridge, stop light, rear-set foot controls, fully adjustable alloy race shocks and externally mounted front fork rebound unit.

“With Japan the birth place of the Super Cub, stepping up to customise one here means delivering a design that punches well above its weight in every aspect,” says Roberts, referring to his striking yet reverent re-imagining. “A concept that stops people in their tracks is one thing, but it's the deep connection and respect to the original machine’s DNA that gives the Firefly endearing timeless character.”

The Honda Cub may be the best selling vehicle in internal combustion history, but performance components are scarce for the first series overhead valve single. Every nut, bolt, bearing and bush, from engine components to front suspension internals, have been re engineered, redesigned or improved from decades old factory blue prints. “Mill and lathe have kissed enough of this lithe steed to leave a HRC factory team envious,” says Roberts.

Half century old engines require as much art as science to coax reliable power increases, so friend and local engine guru Ted’s Special, who’s work graces Honda’s own race collection hall, handled over-sizing and tuning the petite donk to race series regulation maximum 20 per cent capacity increase.

Open carb mouth gleefully gulped in cool mountain air for the run-in and secret shakedown session. Test pilot Yamamoto-san confirmed planted, confidence inspiring handling that holds a line unlike any Cub he’s ever ridden and ergonomics that beg for speed and welcome cornering velocity. Gearing set and jetting sorted, the Firefly went on to break cover and début at the Battle of Bottom Link RACE Series.

We doubt Soichiro Honda’s original team would have ever imagined their humble first series Super Cub transformed into a pole-position-ready racer over half a century later… though we do know they would be proud.