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With its inch-perfect body, OEM-style bodywork, and period-correct graphics, you’d be forgiven for mistaking this Yamaha for a forgotten 90s manufacturing unit prototype. However what it truly is, is a totally bespoke machine with a Yamaha XS400 engine, a complete lot of progressive engineering, and a patented entrance suspension system. Oh, and it was constructed by a hobbyist in a 13-by-15-foot workshop in Slovakia.
“The principle concept of the construct was to make it look as little like a {custom} bike, and as very similar to a manufacturing unit bike, as doable,” says the mad scientist behind the mission, Roman Juriš. “In purely novice situations and with a restricted price range, I couldn’t get it a hundred percent proper.”
Roman’s humility is admirable however completely pointless. The work completed on this Yamaha may fill volumes—and the cohesiveness of the tip product is at a stage that even skilled builders attempt for. Nonetheless, he’s sincere about the truth that getting there was no simple job.
Roman began with a 1984 Yamaha XS400 non-runner, which he promptly stripped and began fabricating a brand new body for. However he shortly fell right into a rut, struggling to correctly visualize the ultimate design. “I attempted to attract totally different variations, however it lacked the lightness {and professional} end that I actually needed,” he tells us.
“Whereas looking for inspiration, I discovered an e-mail deal with for the well-known designer Oberdan Bezzi. To my nice shock, he began speaking with me, and at last despatched me a single, however for me very uncommon, image of a motorbike with a design appropriate for my body.”
As soon as the design was within the bag, the true work started. Roman estimates that he spent 3,000 hours engaged on the mission, unfold over 5 years and two months. “Varied craftsman associates did quite a bit for me,” he provides, “as a result of my workshop is small and I merely don’t have the required equipment and instruments for the whole lot associated to the manufacturing of a motorbike.”
As for the bike itself, it’s onerous to know the place to start. The XS400 motor hangs from a custom-made tubular body through alloy mounting brackets. (The thought of suspending the engine from the chassis was central to Roman’s idea.)
The swingarm is off a Yamaha YZF-R125, which was technically Roman’s third alternative. The primary try concerned fabricating a {custom} tubular swingarm, and the second used an Aprilia unit. In the long run, the YZF-R125 half match the invoice—as soon as Roman had shortened it by 80 mm.
To make the chassis much more distinctive, Roman then shifted the rear shock to at least one aspect as a substitute of leaving it useless middle; a element impressed by the Ducati Scrambler. The 17” laced wheels are repurposed supermoto hoops. Roman despatched the entrance wheel off to a workshop in Austria, who re-laced it to a Honda Transalp hub in order that he may set up twin brake discs.
But it surely’s the entrance finish that’s actually intriguing. Roman calls it “progressive upside-down entrance suspension,” and at the moment holds the European patent (and a one-year worldwide patent) for it. “Acquiring a patent took nearly two years—half a 12 months of preparation, and a 12 months and a half ready for approval,” he tells us.
With out the flexibility to design the entire thing utilizing software program, Roman designed the entrance suspension the old style means. Technical drawings had been adopted by laser-cut metal elements, that had been put collectively to construct a prototype. As soon as that was perfected, the prototype was despatched to a 3rd get together to copy in CNC-machined aluminum.
Roman is hush-hush on the nitty-gritty of the way it all works, however he does cowl the highlights. “It’s progressive, within the sense that for 120 mm of entrance wheel journey, for instance, the fork solely strikes 60 mm. The axis of the entrance wheel is pushed ahead, eliminating the shortening of the wheelbase, and the spring and braking forces are remoted, so the motorbike doesn’t dive below braking.”
Because the setup behaves nearly like a springer fork, Roman additionally needed to construct a parallelogram system for the entrance fender, in order that it strikes flawlessly with the entrance wheel. An LED headlight and small fly display sit greater up, with a Koso sprint mounted to the identical handmade bracket that holds the display. The cockpit additionally wears clip-ons, bar-end mirrors, and the unique Yamaha switches.
For the bodywork, Roman as soon as once more turned to conventional strategies. He used modeling clay to finalize the kinds, then formed the whole lot out of fiberglass. The gas tank is only a cowl, hiding a metallic reservoir beneath it.
A neat under-seat exhaust system finishes off the Yamaha’s ultra-skinny silhouette. Roman occurred upon a deconstructed set of dual headers within the Netherlands, which he put collectively and matched to a pair of aftermarket mufflers. A custom-made tail tidy wraps across the twin cans to host the license plate and mixture LED taillights.
As for the paint job, that got here instantly from Oberdan Bezzi’s design—with a number of tiny modifications. “The body needed to be crimson, like racing Yamahas from the 70s,” Roman explains, “and I needed conventional Yamaha blocks, however in a minimalist model on a white background.”
“The model of the ‘Roadster’ inscription is a tribute to the Jawa 90 Roadster, which was produced in Slovakia from 1967 to 1976. It was a progressive bike that was, to its detriment, means forward of its time.”
Roman additionally left all of the aluminum elements uncooked somewhat than ending the whole lot in, as he places it, “boring black.” He additionally spent numerous hours sprucing the swingarm, and settled on a easy cowl for the seat, after a two-tone cowl with distinction stitching proved to be too busy.
Roman concludes by admitting that it’s unimaginable to make the bike road authorized in Slovakia—however that he added all the required roadworthy frou-frou anyway, to strengthen the manufacturing bike vibe he was going for.
We may pore over the main points of Roman’s creation for hours, however there’s one main element we haven’t talked about—and that’s how rattling good the refreshed XS400 mill seems to be in its new house.
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