The Myth and Mystery of Jean Lehaitre’s 1938 Track-Driven Motorcycle
Inventive Paradox - Long before electric motorcycles and adventure bikes reshaped how we think about two-wheeled freedom, there was a moment in history when inventors dreamed with grease-stained hands and open imaginations. The late 1930s were an age of mechanical optimism — when engineers dared to merge machines that didn’t seem to belong together. Among those restless innovators was Jean Lehaitre, a French creator who asked a simple but radical question: what if a motorcycle didn’t need wheels at all?
A one-of-a-kind motorcycle that moves like a tank — the Tractor-Cycle, created by Jean Lehaitre in 1938. (Picture from: GridOto— original black-and-white photo colorized using Krea.ai)
That question took physical form in 1938 as the Tractor-Cycle, a track-driven motorcycle that looked more like a miniature tank than anything else on the road. The concept was so unusual that Modern Mechanix magazine featured it in its February 1938 issue under the headline “Belt Drive Replaces Wheels on Novel Motorcycle.” The accompanying photo showed Lehaitre himself sitting astride the machine — proof that this wasn’t just a sketch or speculative idea, but a real, working prototype.
Jean
Lehaitre’s track-driven motorcycle replaced conventional rubber tires
with a continuous steel-belt track that looped beneath the frame like a
tank tread. (Picture from: GridOto— original black-and-white photo colorized using Krea.ai)
Lehaitre’s design was a marvel of odd but practical thinking. Instead of the familiar rubber tires of a conventional bike, it used a continuous steel-belt track — a loop running beneath the frame much like a tank tread. This gave the machine exceptional traction and the ability to crawl across rough terrain, climb hills, and handle conditions that would easily defeat ordinary motorcycles. The magazine reported that it could reach speeds of about 25 miles per hour (around 40 km/h), impressive for something so heavy and mechanically complex. Steering, according to the article, was achieved by turning the handlebars to slightly shift the direction of the moving track — a clever adaptation of motorcycle control to an entirely different propulsion system.
Jean
Lehaitre’s second track-driven motorcycle prototype featured small
rubber wheels designed to provide stability during operation.(Picture from: GridOto — original black-and-white photo colorized using Krea.ai)
Though designed primarily for rugged terrain, Lehaitre imagined potential military applications as well. The Modern Mechanix cover even showed an artist’s rendering ofthe Tractor-Cyclefitted with a mounted machine gun, suggesting it could be used for dispatch riding or reconnaissance across bomb-scarred landscapes. While there’s no evidence it ever saw service or entered mass production, the concept aligned neatly with the era’s growing fascination with mechanized warfare and all-terrain mobility.
Jean Lehaitre’s track-driven motorcycle prototype never saw service or mass production, yet its concept perfectly reflected the era’s fascination with mechanized warfare and all-terrain mobility.(Picture from: GridOto)
Lehaitre’s invention wasn’t born in isolation. France had already seen a similar experiment a year earlier — the 1937 Mercier Moto Chenille, another caterpillar-track motorcycle designed to conquer off-road conditions. The Moto Chenille shared the same mechanical ambition: to merge the agility of a motorbike with the endurance of a tracked vehicle. A few years later, Germany would take the idea further withthe NSU Kettenkrad, a half-track motorcycle produced in significant numbers during World War II, used to transport soldiers and equipment across battlefields. Lehaitre’s prototype, in retrospect, seems like a missing evolutionary link between these machines — a French experiment that foreshadowed one of the most distinctive military vehicles of the 1940s.
Although no surviving units, patents, or museum exhibits remain, the evidence from the 1938 publication confirms that the Tractor-Cycle did in fact exist. (Picture from: GridOto)
Today, only the faded pages of Modern Mechanix and a handful of surviving photographs remind us of Jean Lehaitre’s bold idea. There are no surviving units, no patents, no museum displays. Yet the evidence from that 1938 publication confirms thatthe Tractor-Cycletruly existed, at least as a working prototype — not myth, not rumor. It was the product of a time when invention was less about efficiency and more about daring; when one person with tools, time, and imagination could literally reinvent what a motorcycle could be. | GuJC-T4v1TU | rNhJt0uWync |
In the grand narrative of automotive history, the Tractor-Cycle occupies a small but fascinating chapter. It represents that restless human urge to build something different — something that rolls not on wheels, but on the conviction that boundaries are meant to be crossed, even if the road ahead has yet to be made.
That question took physical form in 1938 as the Tractor-Cycle, a track-driven motorcycle that looked more like a miniature tank than anything else on the road. The concept was so unusual that Modern Mechanix magazine featured it in its February 1938 issue under the headline “Belt Drive Replaces Wheels on Novel Motorcycle.” The accompanying photo showed Lehaitre himself sitting astride the machine — proof that this wasn’t just a sketch or speculative idea, but a real, working prototype. 
In the grand narrative of automotive history, the Tractor-Cycle occupies a small but fascinating chapter. It represents that restless human urge to build something different — something that rolls not on wheels, but on the conviction that boundaries are meant to be crossed, even if the road ahead has yet to be made.
