In the relentless pursuit of performance fine-tuning, KSpeed has introduced a drop nozzle kit for the Kawasaki Ultra 300/310 platform that offers racers and serious riders a new level of control over handling and thrust vectoring. Recently made available via Brisbane Kawasaki, the kit is already drawing attention for its versatility and engineering.
What the Kit Offers
At its heart, the KSpeed drop nozzle system is a fully adjustable nozzle assembly designed to replace the stock exit nozzle on Kawasaki’s 300/310 jet pump setup. The core features and specifications as listed by Brisbane Kawasaki include:
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A range of drop angle adjustment from 0° (level) to 10° of downward drop
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A kit of 10 interchangeable exit rings (the 82 mm ring ships preinstalled) to allow precise tuning of the nozzle aperture and flow characteristics
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Support for both left- or right-side steering linkage, with twin cable drop-in holes for steering response tuning
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Compatibility with manual- or cable-trim systems, including support for either short direct cable or long cable with wheel + bracket (all hardware included)
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CNC-machined construction from billet 6061 aluminum with a clear hard-anodized finish, plus stainless steel hardware for durability
Given those specs, the KSpeed drop nozzle does more than simply alter exit geometry—it gives the rider (or tuner) a palette of aerodynamic and hydrodynamic tuning options previously reserved for high-end race craft.
Why a Drop Nozzle Matters
In simple terms, the nozzle controls the direction and velocity of the jet of water leaving the pump. Altering its angle subtly changes how the thrust vector interacts with the hull. Traditional stock nozzles are fixed, leaving riders to rely on trim tabs, ride plates, hull design, or pump wedges to influence bow attitude and stability.
By contrast, a drop nozzle enables active manipulation of that thrust vector—effectively allowing “steering by thrust” in addition to the hull’s response. Combined with steering linkage tuning and trim control, the drop nozzle becomes a powerful tool for dialing in balance, turn-in, and exit behavior under acceleration.
From field experience and prior KSpeed tuning strategy, the benefits are most evident in rough water, aggressive cornering, and mid-range acceleration, where the ability to adjust “how hard” and “where” the thrust is applied has real-world consequences.
KSpeed’s own development philosophy reinforces this approach. In their Stage 1 kit for the Ultra 310 (which uses a pump wedge, intake modifications, and ECU remap), they emphasize nose lift and more consistent flow into the pump as keys to gaining speed and handling improvements. The drop nozzle is an evolution of that same principle—but with far more flexibility.
Fitment, Compatibility & Considerations
Because the KSpeed nozzle is intended for Kawasaki’s 300/310 pump geometry, it bolts up directly to the standard exit without requiring radical alterations. However, some caveats and considerations apply:
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Although engineered for the 160 mm pump on the 300/310, KSpeed’s other drop nozzle designs (for STX / 148 mm systems) use spacer adapters to adapt between pump sizes.
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The trim compatibility is flexible, but riders must decide whether to use a short direct-cable trim line or the longer cable + wheel/bracket setup included.
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Steering geometry and linkage setup become more critical; because the nozzle adjustment also affects where the thrust “pulls,” proper steering alignment is essential to avoid unpredictable behavior.
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Because a drop nozzle makes it possible to push the bow downward (at negative drop) or lift upward (at positive drop), a rider must be cautious in extreme settings, especially at high speed or in chop.
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Interchangeable rings allow tuning for differing water conditions or rider weight—yet ring choice must be harmonized with pump trim, hull setup, and intake geometry.
In short: the drop nozzle offers choice, not cure-alls. Skill and integration with other modifications (intake, ECU, pump wedge, ride plate) remain critical.
What It Can Deliver, and What to Watch For
While direct test data on this specific KSpeed drop nozzle kit is still emerging, its conceptual benefits are supported by broader community experience and KSpeed’s own tuning track record.
For the Ultra 310 platform, KSpeed’s Stage 1 kit (without a drop nozzle) has proven capable of adding about 5 mph over stock top speed in test conditions, while improving midrange acceleration and responsiveness. It stands to reason that integrating an adjustable nozzle would enable further refinements—especially in handling and responsiveness in variable-sea conditions.
Some expected outcomes one might optimize toward:
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Sharper turn-in due to thrust redirection at pivot points
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Better hull balance in chop or cross seas
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Improved throttle transitions as you adjust drop angle under acceleration
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Fine-tuning adjustments to mitigate porpoising or bow bounce at high speed
But potential pitfalls must be respected:
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Incorrect drop settings (too aggressive) could negatively affect directional stability
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Mismatched nozzle ring sizes or trim settings may cause turbulence or cavitation
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Overly aggressive settings at low speed or in tight turns could induce unwanted pull or yaw
Therefore, methodical testing—starting from neutral or minimal drop, then progressing incrementally—is the safest path.
KSpeed’s 300/310 drop nozzle kit is an ambitious piece of performance hardware. It brings a level of adjustability once reserved for elite race craft into the hands of serious enthusiasts. For riders looking to squeeze every bit of controllability from their Ultra platform, the ability to tune thrust angle dynamically is a powerful lever.
However, it’s not a plug-in magic bullet. Success with this kit depends on integration with steering, trim, intake, and hull setup—and patience in dialing each setting. For those willing to experiment, it offers a pathway toward a more precise, responsive, and controllable ride.
