Sprint Filter P08 F1-85 Air Filter for Racing – Yamaha YZF-R3 (2015–2026) K44S F1-85

Nearly every choice in this catalogue can be taken back. Media share a housing, so a weave that turns out to be wrong for the roads actually ridden is a twenty-minute correction at the next service. The K44S F1-85 is the exception on this motorcycle. It requires modification of the airbox, with the housing repositioned to take it, and once that work has been done it has been done. None of which is an argument against the kit — it is an argument for deciding in advance rather than by experiment.

Key Features

• Racing-grade dry polyester at 85 microns, the most open weave in the range
• Rated throughput of 15,000 litres per square metre per second
• Dry in every state: nothing to oil on arrival, nothing to re-oil after washing
• About twice the filtering area of other performance filters
• Installation requires the airbox to be repositioned, so the fitting is a planned job
• Regenerated with compressed air and refitted; two years of warranty from purchase

The one decision here that is not reversible

Anyone who wants this weave without altering anything has a second route: the same 85 micron medium is listed for the R3 under a separate number that occupies the factory panel position. So the K44S F1-85 is not the only way to the material, and it should be chosen for what makes it different — a kit built around a repositioned housing — rather than by default. Whichever way that goes, check the marking on the panel currently in the bike before ordering, because the two entries share a medium and a motorcycle and nothing else.

Who an open weave was drawn for

15,000 litres per square metre per second against the standard weave's 5,050 is a capacity, not a delivery: it is drawn on while a throttle is held wide open and hardly at all otherwise. A 300 cc twin on a public road reaches that state in seconds at a time, which is why the case for this kit is made in a paddock and not on a commute. It is certainly not made in horsepower. An element in an airbox does not add any, and the racing grade lets a little more of the fine fraction through as the price of the flow it offers.

Care and cleaning

Compressed air from the clean side outwards, directed away from the medium rather than into it, handles the ordinary service. Washing is for what air will not shift: hand-warm water, a mild detergent, rinsed until clear. After that the element must dry completely in circulating air — heat guns, radiators and flames all destroy polyester, and a damp panel refitted in a hurry restricts more than the one it replaced. Nothing is ever oiled. The maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Drawn against the Yamaha YZF-R3 of 2015 to 2026, and against no other machine. Since the installation asks for the housing to be repositioned, read the work through before ordering; the Fitment tab holds the model years.