Buell M2 Cyclone S1 Tribute with Flax Fiber Body Panels

Bolting a delicate arrangement of dried flowers to a shaking Milwaukee V-twin sounds like a highly inefficient way to make mulch, but then again, we’ve never seen it tried until now. If you’ve spent any time with a Buell, you know it’s a machine built on a mechanical brute-force ethos: take a torquey pushrod engine, cram it into a rigid frame with radical geometry and hang the suspension underneath. But down in Montauban in southwestern France, Guillaume Coruble decided to wrap that American muscle in an intricate botanical skin.

Guillaume operates under the moniker Genextile. He is a 40-year-old former French military serviceman who has spent the last 15 years specializing in multi-process composite fabrication. His latest project started with a carbureted 1997 Buell M2 Cyclone, but the goal was to capture the ultra-compact lines of the S1 Lightning. What sets this build apart isn’t just the S1 silhouette. It is the material science executed on the bodywork.

The project was initially conceived as a nod to Guillaume’s four-year-old daughter Rose. He wanted to embed real rose petals into the composite to create a floral forged carbon. Material chemistry got in the way, as trapped air in the petals expanded under UV light, causing delamination. Refusing to build a trailer queen that would degrade in the sun, Guillaume ran UV-aging tests on various botanicals. He pivoted to a mix of UV-compatible natural flowers laid over a base of raw flax fiber.

For those who need a refresher, flax fiber is the raw material traditionally spun into linen textiles, but when infused with epoxy resin under vacuum, it transforms into a highly rigid, vibration-damping structural composite. The name L1 ThunderFlower is a deliberate play on words. In French, L1 is pronounced Lin, which translates to flax. It is a sharp linguistic nod, replacing the S in S1 while ThunderFlower replaces Lightning—a fitting moniker for a roaring American twin clad in dried flora.

All composite work was handled in-house. Guillaume pulled molds from an original S1 and utilized vacuum infusion to achieve the high mechanical strength required for the body panels. The kit is laid up using French flax fiber sourced from the Terre de Lin cooperative in Normandy and bonded with bio-sourced epoxy resin. It is a grueling manual process. The dried flowers and gold leaf inlays were positioned by hand before receiving multiple coats of epoxy glaze applied with a brush. The final polish was executed entirely by hand to ensure a gloss finish that highlights the raw weave of the flax.

The trick composite work would be enough for most of us, but the transformation goes beyond the skin. Guillaume modified the M2 frame to accept a custom carbon and epoxy subframe carrying the S1 profile. The suspension was upgraded utilizing an inverted front fork, swingarm and central shock sourced from a Buell X1. Rolling stock consists of forged aluminum Performance Machine wheels, a popular upgrade when the Buell was new. 

At the center of the chassis sits a fully rebuilt example of Erik Buell’s 1203 cc V-twin engine with just 500 kilometers on the clock. Guillaume retained the desirable original gray cylinder heads known for their smaller valves, which offer better intake velocity and mid-range punch. Induction is handled by a Mikuni HSR42 carburetor drawing air through a Force Winder intake. Spent gases exit via a Vance & Hines exhaust while a Buell Race ignition box handles the spark. From there, Guillaume mixed and matched domestic and export pulleys in the final belt drive to sharpen acceleration further.

The front end is dominated by an LED headlight equipped with an integrated gyroscope. The same hardware utilized by ARCH Motorcycle, the light beam physically pivots to match the bike’s lean angle in the corners. Above it sits a set of Rizoma 28 mm straight handlebars clamped with OMP billet aluminum controls for the clutch and front brake. The throttle is a short-pull unit from Buellmachine alongside official Buell grips.

Guillaume leaned heavily into Motogadget electronics. The bike features a keyless m.lock ignition, a custom machined starter button and a digital speedometer mounted on a custom carbon gauge face. The seat is stitched in synthetic crocodile leather, which extends down to a custom right-knee heat shield formed from carbon and epoxy. The exhaust header shield uses invisible fasteners and is laid up with high-temp epoxy resin, raw flax, carbon and Kevlar.

Additional hard parts come courtesy of Buellmachine, including a machined pulley cover, shortened cam cover, custom engine mounts and cylinder head bolt covers. Lighting is kept minimal with 3-in-1 LED turn signals at the rear alongside an integrated Buell Ulysses taillight.

Without the advanced composite work, Thunderflower would still be a pretty trick Buell, but it’s the intersection of Guillaume’s personal and professional interests that bring it to the next level—earning a nod of approval from Erik Buell himself. Fortunately, this wouldn’t be the last time his day job bled into his garage hobbies. 

Back in 2020, he was manufacturing composite components for communication and space observation satellites. When Brough Superior began developing the Aston Martin AMB001 just down the road in Toulouse, they knocked on his door. Guillaume managed to convince his aerospace management to pivot their resources toward the motorcycle sector, ultimately manufacturing the first 30 carbon fiber body kits for the turbocharged Aston Martin using space-grade materials. 

Now that’s something to hang your hat on. 

Genextile | Facebook | Instagram | Photos by Manon

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