Diamond Atelier XSR900 'Aeon'
The Diamond Atelier XSR900 'Aeon' is a custom motorcycle collaboration between the Munich workshop Diamond Atelier and Dutch watchmaker TW Steel, built on a factory-fresh Yamaha XSR900. The concept is rooted in a single idea: that the internal workings of a machine are as beautiful as its exterior, an approach Diamond Atelier borrowed from watchmaking culture and translated directly into motorcycle design. The result is one of the most precise and visually distinctive custom builds to come out of Germany.
Rethinking the Yamaha XSR900 from the frame up
Diamond Atelier, based in Munich, has built its reputation on aggressive minimalism and uncompromising craftsmanship. Their approach to the XSR900, a Yamaha platform that already earned a strong following for its neo-retro design, was to strip it further and reveal what lives beneath the surfaces other builders leave hidden.
The first task was to remove all existing cabling, totaling around 328 feet of wiring, and reroute it invisibly. This is not a minor modification: it demands a complete electrical rethink of the machine. Designer Julian Weber, whose influence on the Aeon comes partly from Japanese custom car culture, shaped the visual language of the build around that absence. Fewer visible lines. More intentional negative space.
The fuel tank cutout: aggressive design, subtle execution
The most immediately striking feature of the Aeon is the fuel tank. A large cutout has been carved into the tank, creating a skeleton silhouette that exposes the frame beneath. Below that void, the K&N air filters sit in plain view, mounted deliberately as design objects rather than hidden components. The cutout reduces tank capacity to around 3 liters, which is tight, but Diamond Atelier accepts that trade-off without apology. A motorcycle this visible does not go unnoticed at petrol stations regardless.
Additional mechanical upgrades include a custom exhaust, lowered forks, and a Wilbers Blackline rear shock. Because the Yamaha XSR900 donor was factory-fresh, many of the base components did not need replacement. That gave the team room to focus entirely on transformation rather than repair.
The TW Steel timepiece hidden in the headlight fairing
The collaboration with TW Steel adds the build's most unusual detail. Where a headlight would normally sit, the Aeon conceals a TW Steel Aeon timepiece beneath a hinged headlight-flap. Open the flap and there is a watch where there should be a lens. It is the most direct expression of the brief: a motorcycle that pays visible tribute to watchmaking, with the timepiece literally embedded into the machine it inspired. TW Steel released a special edition watch to accompany the build's reveal.
A rare cross-industry collaboration done right
Watchmaker and motorcycle garage collaborations are uncommon, and the ones that exist often reduce to badge placement or cosmetic finishes. The Aeon avoids that entirely. Diamond Atelier used TW Steel's craft vocabulary as a design brief: expose the mechanics, make the internals beautiful, treat precision as aesthetics. The result is a motorcycle that combines a boldly aggressive silhouette with the fine detail work more commonly associated with Geneva ateliers than Munich garages.
Explore Diamond Atelier custom motorcycles on TheArsenale, including the DA#5 Suzuki DR650, another landmark build from the Munich workshop. For more of the finest custom motorcycle design available, browse the TheArsenale Motorcycles collection.
