Sprint Filter P08 F1-85 Air Filter for WorldSBK Racing – MV Agusta F3 800 (2012–2026) R135S F1-85-SBK

An airbox is not simply a container. It is a tuned, sealed volume that shapes induction noise, and on a road-registered motorcycle it forms part of the arrangement the machine was approved in. R135S F1-85-SBK requires that box to be modified and the element repositioned, which makes it different in kind from anything else on an F3 800's parts list. This one alters the motorcycle, not only what sits inside it.

Key Features

• WorldSBK-specification element on a carbon fibre frame, in the F1-85 racing cloth
• Requires modification of the airbox and relocation of the element — not a service swap
• 85 µm and a rated 15,000 l/m²/sec, the freest-flowing medium in the Sprint Filter range
• Dry polyester with no oil at any stage, so nothing can travel onto the intake sensors
• Washable and reusable, regenerated with compressed air from the clean side
• Two years of warranty from purchase; built to last as long as the motorcycle

The part of this decision that is not about air

Reworking a housing is permanent in a way that swapping an element is not, and it is worth thinking about before the first cut rather than afterwards. The sealed volume and its mouth are what the approved intake arrangement consists of; changing them changes it. What the rules are on that varies by country and by how the machine is used, so it is worth checking against the registration the bike actually holds. Where the F3 800 in question is a road bike and nothing else, the standard element in the standard box is the right answer, and there is nothing timid about arriving at it.

What the racing cloth adds on top

The usual direction of travel is finer cloth holding more and flowing less. This medium goes the other way: 85 µm is coarser than the standard 80, and the rated flow is around three times as high. That reserve is only spent while the throttle is held wide open, which on a public road happens in seconds rather than minutes. It is also the dearest of the three kits listed for this machine, close to six times the standard road element. None of it makes a standard F3 800 stronger — an air filter cannot, and this page will not pretend otherwise.

Care and cleaning

R135S F1-85-SBK is regenerated, never renewed. Start with a compressor line on the clean face, pushing outward so that everything the weave caught leaves by the route it came in on. If the cloth still looks loaded, tepid water and a mild washing-up liquid will lift the rest; rinse until what comes through is clear. Then let it stand in open air until it is dry the whole way through. Never hurry that with a hot air gun, a radiator or a flame, since heat is the one thing this material will not tolerate. It goes back dry and untreated. Full instructions sit in the Downloads tab.

Fitment & Compatibility

Specified for the airbox of the MV Agusta F3 800 catalogued from 2012 to 2026, after modification. The second entry on this number is the F3 675 of 2012 to 2021.