The facts.
| Model | JP ES 024 |
|---|---|
| Manufacturer | JetPrime |
| Material | CNC-milled Ergal 7075 |
| Fits | Kawasaki Ninja 400 (2018–2024) |
| Installation | Plug-and-play, no wiring harness modifications required |
| Fitment | Kawasaki Ninja 400 (2018–2024) |
| Road approval | None — closed-circuit and race use only |
DescriptionThe whole story▼
The JP ES 024 shuts the Ninja 400's KLEEN ports in the cylinder head with a machined blank.
Key Features
- Kawasaki Ninja 400 (2018–2024)
- Blanks the secondary air ports in the head
- Machined from solid aluminium
- O-ring sealed, no jointing compound
- Original fastener positions
- Standard housing refits at any time
Fourteen Litres
Enough for a real day rather than a track session, which says plainly that Kawasaki expected these to be ridden to work as well as around a circuit.
Nissin Calipers
A single 310 mm disc at the front with a modern caliper. It is adequate for the weight and the performance, and nobody has ever complained about it seriously.
Not the Electrical Half
The controller monitors its solenoid regardless of what is bolted to the head, so the circuit still needs its own eliminator to keep the panel clear.
A Cracked Reed's Signature
Soot inside the airbox and an element discoloured well before its interval. It is almost always found while chasing something entirely unrelated.
On a Naked Kawasaki
Kawasaki leaves the motor exposed on the naked models, so whatever is bolted to it is part of the design whether it was meant to be or not. A turned cover belongs there in a way a blanked-off pipe never does.
What the Reeds Do
They allow air in one direction only, so exhaust pressure cannot push gas back towards the filter. When one cracks that protection disappears and the evidence turns up inside the airbox.
On an Older Motorcycle
The reeds have been heat cycling for a decade and are close to the end of their life whether or not they have failed yet.
Nothing Structural
The housing carries no load and its removal affects no part of the head's sealing or cooling. It is genuinely a bolt-on component.
The Bike That Sold the Class
Kawasaki outsold every small sports rival for years with the Ninja 400 and made the category respectable again. That volume is why the parts supply for it is so good.
Fitment and Compatibility
- Kawasaki Ninja 400 (2018–2024)
Specifications
| Model | JP ES 024 |
|---|---|
| Manufacturer | JetPrime |
| Material | CNC-milled Ergal 7075 |
| Fits | Kawasaki Ninja 400 (2018–2024) |
| Installation | Plug-and-play, no wiring harness modifications required |
What's includedEverything in the box▼
- 1x block-off plate
FitmentWhich bikes this fits▼
- Kawasaki Ninja 400 (2018–2024)
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Measure your head circumference about one centimetre above your eyebrows and compare it with the size chart on this page. Between sizes? Choose the smaller one — the padding beds in with use.
Yes — it’s tested and approved to the current ECE 22.06 standard and road-legal across the EU.
Most of our touring and sport helmets are Pinlock-ready and many include the insert. Check the ‘What’s in the box’ section on this page for this model.
Yes — the cheek pads are channelled so the arms of your glasses slide in comfortably.
Take out the washable lining and hand-wash it in lukewarm water. Clean the shell and visor with a soft cloth and water only — never solvents.
Our team will personally help you choose the right gear or part — around 24h for a reply.