2007 Kawasaki Ultra 250X

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After stunning the motorcycling world with the launch of the Ninja ZX-14 flagship, Kawasaki extends its high-performance domination into the realm of personal watercraft. The Kawasaki Jet Ski Ultra 250X is the quickest and the most powerful ski jet ever built, and there’s no surprise on that being a Kawasaki ski jet.


Kawasaki Ultra 250X

The Ultra 250X has a supercharged and intercooled four-stroke, DOHC, four valves per cylinder, inline four-cylinder that delivers 250 hp for astonishing acceleration. The engine, jet drive and hull incorporate racing technology that allows it to deliver the awesome acceleration of a drag racer, and help ensure excellent hook-up – even in rough water. With a 1,498cc marine engine the Ultra 250X produces power comparable to a normally aspirated high-performance three-liter engine, thanks to the addition of a Roots-type supercharger. The Ultra 250X overcomes this with the use of a large-capacity intercooler. The 250X’s supercharger compresses the air to a maximum boost pressure of 11.4psi. This compression heats the intake charge to extremely-high temperatures, which could limit the engine’s power output. However, the 250X’s large-capacity intercooler cools the intake charge back down to ambient temperature or even less – ideal for producing maximum power. The stunning acceleration of the Kawasaki Ultra 250X is augmented by a huge 155mm jet pump featuring the largest PWC impeller and nozzle Kawasaki has ever produced. This pump was specially designed to deliver predictable thrust and good “traction,” even when riding on rough water. The pump uses eight guide vanes (instead of the six used on previous models) to regulate the flow of water from the impeller for efficient and powerful propulsion. To suit the 155mm jet pump a new, larger impeller was designed, offering improved “bite” in the higher speed ranges. The sophisticated three-blade design not only delivers high performance, but also provides smooth and quiet operation.


Kawasaki Ultra 250X

Extensive research and refinement has allowed Kawasaki to design a brand-new hull which is just as comfortable in rough conditions as in calm. Even at high speeds, rough water can do little to deter the Ultra 250X. The hull is made from fiberglass reinforced plastic. The 22.5 degrees deep-V hull includes carefully designed sponsons and chines for enhanced straight-line stability and precise cornering. All the research Kawasaki made resulted in a precise and easy to handle ski jet.

Test drive

If the power and the design of the Kawasaki Ultra 250X didn’t impress you yet riding this ski jet will definitely blow your mind. Kawasaki designed the Ultra 250X’s hull to lean into corners like a motorcycle helping the passengers to stay centered and the driver in control during cornering. This ski jet can reach a top speed of 65-70 mph, making it the fastest on the market. The only problem, if you can name it that, is that the Ultra 250X burns a lot of fuel. The 20.6 gal fuel tank will keep you riding for approx. 7 hours. But I don’t think that’s a serious problem! The pleasure those 7 hours of hard riding the Kawasaki Ultra 250X can’t compare with anything!

Kawasaki Ultra 250X


The Kawasaki Ultra 250X offers performance and excitement that are unmatched by any other watercraft. This will impress you after the first ride and make you dream at your next ride on the Ultra 250X.


Supercharged and intercooled, 1,498cc, liquid-cooled, in-line four-cylinder engine
Most powerful production PWC engine in the world
The 83.0 x 69.2mm bore and stroke are the same as the JET SKI STX®-15F’s powerplant
Compression ratio is lowered to 7.8:1, to minimize detonation at high-boost pressures
Inconel exhaust valves are fitted for superior heat resistance and enhanced reliability (Valve sizes are: 33.4mm intake / 28.3mm exhaust)
The engine’s over-rev capability has been raised by 700 rpm (redline is 8,900 rpm)
Precise power adjustments are easy with a throttle lever that is designed to prevent finger fatigue on longer rides

Roots Type Supercharger
The Roots type supercharger design produces large amounts of boost even at low rpm, for instant and powerful acceleration right off of idle
Force-feeds the engine two liters of air with every revolution, providing a stable supply of high-pressure intake air at all rpm
Provides a very flat and meaty torque curve with step-free power across the rev range and none of the lag associated with turbochargers
Produces a maximum of 11.4psi of boost pressure
Produces more low RPM boost than competitive or aftermarket systems
To prevent over boosting at low and medium rpm, two different air bypass valves (ABV) are used
The smaller ABV releases low amounts of excess pressure build-up, for precise boost management
The larger ABV is used when excessive boost pressure is accumulated, to maintain an even intake pressure even when giving full-throttle from idle

Air-to-Water Intercooler
Efficiently cools the high-pressure intake air
Cooler air results in higher combustion efficiency and high engine output
Liquid-cooling allows the intercooler to maintain consistent thermal performance

Fuel Injection
New, high-flow fuel injectors with four orifices are fitted to complement the increased power output and improve combustion efficiency
Single throttle body features a large 60mm bore diameter

The Ultra 250X features a 4-into-2-into-1 powerboat-style exhaust system, which routes the exhaust pipe upwards.
Allows the smoothest path for exhaust gases, maximizing exhaust efficiency

Jet Pump
To efficiently convert the Ultra 250X’s massive horsepower into thrust, an all-new, large-diameter 155mm jet pump was designed
Developed based on feedback from Kawasaki’s race machines, this pump was specially designed to deliver stable output and good “bite,” even when riding on rough water
The reverse lever has been moved from the right side to the left side for easier operation

To suit the new 155mm jet pump, a larger impeller was designed, offering improved thrust in the higher speed ranges 
The sophisticated three-blade unit delivers both high performance and quiet operation

Guide Vanes
To suit the new jet pump, a new eight-vane intake guide is used. These guide vanes smooth and regulate the flow of water from the impeller for efficient and powerful propulsion
Eight guide vanes provide superior “traction” compared to the older six-vane system

Ride Plate
Features a groove from the center to the rear of the ride plate, to enhance straight-line stability


Kawasaki Ultra 250X

The new hull was designed based on feedback from Kawasaki’s IJSBA championship winning racing machines.
Specially designed to cope with the engine’s horsepower
Offers a combination of high stability and responsive handling in both calm and rough-water conditions
Delivers the neutral handling and turning characteristics that made Kawasaki JET SKI watercraft famous
The new super-strong hull is 250mm longer, to ensure stable handling performance with the larger, more powerful engine
The lower hull is specially designed to distribute the engine and power delivery loads over a wide area
Although it has a similar V-shape to the JET SKI STX-15F, the Ultra 250X’s hull enables a high bank angle, for motorcycle-like turning performance. This reduces the side G-loads imposed on riders during turns
The V-angle at the bottom of the hull has been changed to 22.5° to help prevent spinouts during sharp turns and to provide a smoother ride in rough water
To avoid concentrating heavy components towards the rear, the battery is located inside the front storage area near the center of the machine. This remote location also frees up space inside the engine bay

Bond Flange & Bumper

The bottom of the hull slants upwards steeply from the center section to the bow, allowing the Ultra 250X to penetrate swells and waves with less shock. At low speeds the result is extreme stability; at higher speeds the Ultra 250X’s massive thrust enables the hull to push through waves rather than bounce over top of them

Newly developed sponsons extend further from the hull, providing stable straight-line performance while helping to retain the narrow hull design. They also contribute significantly to the Ultra 250X’s excellent maneuverability when changing direction (particularly at higher speeds

Quattro KSD
Ridges across the bottom of the bow, Kawasaki Splash Deflectors deflect water splashing forward from under the hull. To reduce spray during high-speed turns, the earlier triple splash deflector now has one more deflector mounted at the top. Whether turning or blasting straight ahead, at high speeds or low, the Quattro KSD minimizes spray, allowing greater rider concentration and a drier ride

Kawasaki Smart Steering®/SLO-Mode

Kawasaki Smart Steering (KSS®) is equipped to help new riders better enjoy the performance of this remarkable machine
Smart Learning Operation (SLO)-Mode function allows newer riders to become familiar with the handling and response of this JET SKI watercraft at a more relaxed pace before unleashing the full power of the Ultra 250X. Two separate keys (one for SLO-mode, one for full-power operation) help prevent confusion over which setting is in use

Comfort and Convenience
Five-way adjustable handlebars allow operation while standing or sitting and are designed to suit a wide range of riders.
Relatively narrow seat is comfortable for either stand-up or seated riding, or when riding with passengers
Ergonomic deck design gives plenty of legroom without necessitating a high seat, for rider-friendly seating accommodations
A long rear boarding step makes it easy to climb on board, and the step retracts inside the bumper to prevent damage
A quick and easy under hood hose connection allows nearly silent cleaning system to flush sea water out of the engine
Mirrors are mounted to the upper deck to facilitate opening of the hatch cover

Capacious Storage

Kawasaki Ultra 250X

The large-capacity, fully sealed 53 gallon storage area has plenty of room for recreational equipment. A detachable storage tray is also fitted
Mounted on the center console is a detachable drink holder with space for two drink bottles
A compact storage area is integrated with the under-seat rear grip and ideal for small items

Increased Fuel Capacity
Offering more fuel capacity than any machine in its class, the Ultra 250X’s 20.6 gallon fuel tank holds 3.7 gallons more than the JET SKI STX-15F watercraft


Engine: Supercharged and intercooled four-stroke, DOHC, four valve per cylinder, inline four-cylinder
Displacement: 1,498cc
Bore x stroke: 83.0 x 69.2mm
Compression ratio: 7.8:1
Induction system: Roots-type supercharger with air-to-water intercooler
Maximum boost: 11.4 psi
Maximum horsepower: 250hp @ 7,750 rpm
Cooling system: Inducted water
Fuel system: Digital fuel injection
Ignition: TCBI with digital advance
Starting: Electric
Lubrication: Semi-dry sump system
Coupling: Direct drive from engine
Propulsion system: 155mm jet pump, axial-flow, single stage
Impeller: Three-blade, oval-edge stainless steel
Thrust: 1,524 lbs
Seating capacity: Three-person
Load capacity:
496 lbs
Fuel capacity: 20.6 gal
Storage capacity: 53 gal
Dry weight: 903.8 lbs
Overall length: 132.7 in
Overall width: 46.9 in
Overall height: 45.3 in
Color Choices: Sunbeam Red/Sunbeam Red, Valiant Blue/Metallic Phantom Silver
11,499 USD

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