Sprint Filter P14 Air Filter for Dusty Conditions – Bimota KB399 (2026) PM164P14

A Bimota is a small-series chassis around a mass-produced engine, and the intake belongs firmly to the second half of that description. The KB399 breathes through the same airbox as a family of eleven machines, which is good news for an owner: the one part of this motorcycle that will be needed regularly is not a small-series part at all. What changes is the attitude of the person servicing it. Nobody buys a hand-built frame and then takes chances with what goes into the engine inside it. The Sprint Filter P14 PM164P14 suits that attitude — the fine end of the range at 14 microns, dry, never oiled.

Key Features

• The medium filters at 14 microns and flows 1,800 l/m²/sec
• Never oiled — no film that can travel onto throttle bodies or intake sensors
• Roughly double the filtering surface that other performance filters bring
• Drops into the standard airbox in place of the original — no modification, no remap
• Designed to last the life of the motorcycle; warranty of two years
• Washable and reusable, and cleaned with compressed air from the clean side

Small-series chassis, series-production intake

The distinction is worth drawing because it decides where an owner's attention should go. Anything unique to the KB399 is worth treating carefully, because replacements will not be quick. The airbox and its element are the opposite: shared, in production, and available on the same terms as for any of the eleven machines that use them.

Why nothing oiled goes near it

Oiled filters hold particles in a tacky film, and that film can move under a strong enough airflow — onto throttle bodies, onto intake sensors, onto valve stems. On any modern injected engine that is an avoidable risk; on a machine bought precisely because its owner cares about how it is put together, it is an odd risk to accept. The P14 catches by weave alone. It goes in dry, comes out dry, and is cleaned with air rather than with anything that has to be applied afterwards. The trade being made is flow: 1,800 l/m²/sec against the 5,050 of the standard P08, bought in exchange for filtering at 14 microns instead of 80. For a KB399 ridden on the road that is a sensible direction. For one used hard on track, the P08 or the F1-85 racing medium is the better balance, and the airbox takes either without modification.

Care and cleaning

Compressed air, from the clean side and directed outwards, is the service, and on dusty roads it is worth repeating between formal intervals rather than saving it up. When the element has taken on more than air will shift, lukewarm water with a mild detergent and a rinse until the water runs clear brings it back; it then dries fully in air, never with heat and never with a flame, and is refitted dry. There is no oiling stage at any point in its life. The Sprint Filter maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Made for the Bimota KB399 for 2026. The same PM164P14 element covers eleven machines sharing this airbox design; the complete list is in the Fitment tab.