Sprint Filter P08 Air Filter for Road & Track – Kove 321RR (2021–2026) PM242S

A small-capacity sports machine is ridden in a way a large one never is, and the difference lands squarely on the air filter. A litre bike spends a road ride using a fraction of what it has; the 321RR is used up — wide throttle, high revs, long stretches near the top of the range, because that is where a machine of this size does its talking. The intake therefore works hard for a much larger share of the riding time than it does on a bigger engine, and any resistance sitting in the airbox is paid for during that share rather than at some rare peak.

Key Features

• Single-layer dry polyester fabric filtering at 80 microns, the standard Sprint Filter road and track medium
• Rated material flow of 5,050 l/m²/sec, on roughly twice the filtering surface of other performance elements
• Never oiled, so there is no treatment to reapply and nothing that can travel downstream onto a sensor
• Replaces the original panel inside the standard airbox with no modification and no remap
• Washable and reusable, built by Sprint Filter to last the life of the motorcycle
• Two years of guarantee from the date of purchase

Where the resistance is actually felt

Every filtering element resists the air passing through it, and every element resists more as it fills. On an engine that is asked for most of what it has for most of the ride, that rising figure is not a footnote — it sits in the part of the operating range the rider uses constantly. A dry fabric element is regenerated instead of replaced, which means the resistance can be returned towards where it started whenever the rider decides to, rather than drifting quietly upward until the next service. That, and not a power figure, is the argument. An element inside an otherwise standard airbox does not make a standard machine noticeably faster, and nobody should buy one expecting that.

The middle setting of three

Kove lists this airbox with three media, and the P08 is the one drawn for exactly the mix a road-registered 321RR sees: public roads with track days in among them. The other two sit either side of it. Finer weave means more retention and less flow; coarser means the reverse. It is a trade with two directions, not a ladder with a top rung, and the 80-micron fabric here is the setting that gives up least on either side.

Care and cleaning

Service is a workbench job with no consumables. Compressed air, applied to the clean face and driven outward, lifts the load back off the fabric; where the element has been in service through a wet, gritty winter, lukewarm water with a mild washing-up detergent and a careful rinse does the rest. The PM242S is then dried in open air — never with a heat gun, never near a flame — and refitted dry, with no oil of any kind. The full maintenance sheet sits in the Downloads tab of this page.

Fitment & Compatibility

Fits the Kove 321RR built from 2021 to 2026 in the standard airbox. The same element also serves the NK321R of the same years, so two machines share this part number; the Fitment tab lists both.