Sprint Filter P08 F1-85 Air Filter for Racing – Kawasaki Ninja 500 / EX 500 (2018–2026) PM164S F1-85

The F1-85 medium assumes a way of working. In a paddock an air filter gets looked at between sessions, cleaned when it wants it and swapped without discussion when it does not, and the specification was drawn for exactly that setting: 85 microns and 15,000 l/m²/sec buy airflow by giving up retention, and giving up retention is affordable when somebody has the airbox open constantly. A road-registered Kawasaki Ninja 500 arrives with no such rhythm attached. Fit the PM164S F1-85 to one and you have bought half a system; the other half is a habit you must supply yourself.

Key Features

• The racing weave of Sprint Filter's dry polyester family: 85 microns, run without any oil
• 15,000 l/m²/sec of airflow, three times the rate of the standard P08 in the same airbox
• Retention measured at 95.22 per cent on 100-micron particles, against 93.13 per cent for the P08
• About twice the cloth of a conventional performance filter, folded into the series panel shape
• Goes into the untouched airbox — no cutting, no spacers, no revised map
• Washed and refitted rather than thrown away; two years of warranty

Which half of the exchange you spend

A parallel twin licensed for the road has a broad, low working range, and the point at which the filter medium becomes the term that limits airflow lies right at the top of a rev range this engine only visits. So the debit runs in every second the engine is turning, while the credit is drawn in a handful of them. On a machine that races, that arithmetic can still land the right way up, because short oil intervals and constant inspection cover the filtration side. On one that commutes, it does not.

The proportion nobody quotes

The racing element for this airbox is listed at roughly two and a quarter times the standard P08, and about three times the P14 that shares the same shape. That ratio belongs in the decision because it is the part people skip. None of the three media makes a standard Ninja 500 noticeably stronger; what separates them is where each one sits on the retention-against-flow line. If the honest answer is that the bike does trackdays occasionally and rides to work the rest of the year, the standard P08 is the sensible cross of shape and material, and the money is better spent elsewhere.

Care and cleaning

Blow the element through with compressed air from the clean side, so what is held in the weave is pushed back out the face it entered. Where air alone leaves a mark, lukewarm water and a trace of mild detergent will lift it; rinse until the water is clear. Dry it fully in moving air and nothing else — no heat gun, no radiator, no flame — and fit it dry, untreated, exactly as it came. Racing use means doing this far more often than a service book would suggest. The Sprint Filter maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Shaped for the standard airbox of the Kawasaki Ninja 500 / EX 500 built from 2018 to 2026, and listed for eleven machines that share it, the Bimota KB399 among them. The full list is in the Fitment tab.