Sprint Filter P08 Air Filter for Road & Track – Kawasaki ZX-4R (2023–2026) PM164S

A road-legal four-cylinder 400 exists in the current emissions era only because everything about it is calibrated tightly. The ZX-4R breathes, meters and burns to a specification with very little tolerance built in, and the electronics that manage it depend on measuring the incoming air accurately rather than approximately. The Sprint Filter P08 PM164S is a dry medium: it is never oiled, and there is therefore nothing in it that can travel downstream to where the sensors live.

Key Features

• Dry polyester with no oiling step in its life — nothing that can migrate downstream onto sensors or throttle bodies
• A filtering surface roughly double that of other performance filters
• Reusable: the element is washed and refitted rather than replaced, with compressed air as the routine
• Polyester thread from ø 22 microns, and an aperture that is calibrated rather than pressed out of pulp
• Standard airbox, original position — no modification, no remap, no change to homologation
• The warranty runs two years from the date of purchase

Why an oiled filter is the wrong choice on this engine

Oiled cotton gauze filters by holding a tacky film on the fibres, and that film is only reliable when the oiling is exactly right. Over-oil it, or fit it before it has fully dried, and some of that oil migrates with the airflow onto the surfaces that come next — sensors and throttle bodies among them. A contaminated sensor does not fail cleanly; it reports a value that is slightly wrong, and a tightly calibrated engine acts on it. The P08 removes the question entirely. There is no oiling step, there never has been, and a correct service ends with a dry element fitted dry.

Nothing for the calibration to relearn

The element sits in the original position in the standard airbox and leaves the tuned volume, the intake tract and the noise approval exactly as they were. No remap is required and none is implied. What changes is the medium itself: roughly twice the filtering surface of other performance filters, and a restriction that is restored by cleaning instead of drifting upwards until the next replacement. On an engine this precisely set up, keeping the baseline where the factory put it is more valuable than moving it.

Care and cleaning

In order: compressed air first, from the clean side and working outwards, which is what a normal service consists of. Water second, and only when the element deserves it — lukewarm, with a mild detergent, rinsed until it runs clear. Air third, and nothing but air: the element dries fully on its own, never with heat and never with a flame. Then it is refitted dry and unoiled, exactly as it came out of the box. The Sprint Filter maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Made for the Kawasaki ZX-4R, 2023 to 2026. The same PM164S element serves eleven machines built around this airbox; the complete list is in the Fitment tab.