No crown just performance

Belassi and Kaiser Boats Begin a Joint Journey on Jet Propulsion

At Belassi, we strongly believe that the most meaningful collaborations don’t start with contracts, but with shared values. A similar way of thinking about performance, craftsmanship, and the courage to question existing solutions.

This belief led us to a new collaboration with Kaiser Bootsmanufaktur, a German boat builder known for custom, performance-oriented jet boats built with a level of hand craftsmanship that is becoming increasingly rare.

How the dialogue started

In 2024, while visiting the Tulln Boat Show, a short conversation turned into a recommendation. A neighboring stand from Florian Helmberger (Frauscher, a well-know name for gentlemen on the water). A handshake. And then a discussion with Jürgen Kaiser, the man behind Kaiser Boats. A few emails and calls later, a clear idea emerged, explore what happens when a modern, compact high-power jet engine meets a boat designed by human hands, for humans.

The collaboration is centered around engine supply and joint development, with a strong focus on jet-pump optimization. For the first time, Kaiser integrates a plug-and-play inboard jet solution delivering this level of performance.

The boat involved in this first edition is the Kaiser 580, a 5.8-meter jet boat with a dry weight of just 340 kg, designed to carry up to five people. Traditionally powered with significantly lower output, the platform now integrates Belassi’s 400 hp turbo engine (98 octane, stock version), delivering a step change in power density and packaging.

To put it into perspective, the previous configuration used an outboard delivering around 150 hp with a higher system weight. The Belassi solution offers 400 hp at just 118 kg, while moving to a fully integrated inboard jet architecture.

“I'm really excited about this project! I've been looking for a drive system like this for a very long time.”

Why this combination works

Kaiser builds boats with a clear performance mindset, but also with an uncompromising approach to design and craftsmanship. Many of their hulls are still built using wood, shaped by hand, refined through experience rather than automation. It’s a philosophy that resonates deeply with us.

At the same time, Jürgen is not only a boat builder. His background spans jet propulsion, outboard, inboard, and electric systems, making him a valuable development partner, especially when it comes to refining jet-pump behavior and real-world efficiency.

From the Belassi side, the engine was designed from the beginning as a jet-propulsion power unit. Its compact footprint, dry-sump lubrication, and stable oil supply under high lateral loads make it particularly suited for aggressive jet applications and compact hulls.

reducing friction for builders

This collaboration is not only about power. It’s about reducing friction for boat builders.

For the Kaiser 580, Belassi provided full integration support, including engine mounting solutions, 3D CAD data, wiring architecture, and access to new after-sales tools such as the 3D spare parts system. As a result, the build time of the boat was reduced by approximately 20%, allowing Kaiser to focus on hull development and future concepts rather than powertrain complexity.

First edition, not the final word

At this stage, the project is still in its first edition. Simulations show promising results, and real-world testing is the next step. A detailed case study with measured data and performance figures will follow once the boat hits the water.

The first public appearance of the Kaiser 580 with Belassi power will take place at the Tulln Boat Show, from 26 February to 1 March, where both teams will be present.

For Belassi, this collaboration represents exactly the type of dialogue we aim to build with jet-boat builders and compact OEMs, engineering-driven, flexible, and focused on solving real problems rather than selling generic solutions.

All right, now if you've made it this far, you deserve to know.
The man on the left in the photo above is Wilhelm II, the last German Emperor and next to him Franz Joseph I, Emperor of Austria, King of Hungary, and the ruler of the other states of the Habsburg monarchy from 2 December 1848 until his death in 1916.