Sprint Filter P08 F1-85 Air Filter for WorldSBK Racing – MV Agusta F3 675 (2012–2021) R135S F1-85-SBK

Two separate changes are bundled into R135S F1-85-SBK, and they are worth pulling apart before anything is ordered. The first is mechanical: a larger element on a carbon fibre frame, which is why the airbox has to be modified and the filter repositioned. The second is the medium: the F1-85 racing cloth in place of the standard P08, 85 µm at a rated 15,000 l/m²/sec against 80 µm at 5,050. Alter both at once and nothing that follows can be attributed to either.

Key Features

• Carbon fibre framed WorldSBK assembly carrying the F1-85 racing weave
• Installation requires modification — the element is repositioned inside the series housing
• 85 µm aperture at a rated 15,000 l/m²/sec, roughly three times the flow figure of the P08 cloth
• Dry polyester from beginning to end: never oiled new, never re-treated after cleaning
• Around twice the filtering surface of other performance filters
• Cleaned instead of replaced, with two years of warranty from the date of purchase

Keep something to compare it against

The 675 was catalogued to 2021 and there is no later version of it. Whatever goes in now is what the machine carries for the rest of its life unless somebody unpicks it, and housing work is not unpicked by refitting a panel. So the practical advice here is small and dull: keep the original element, labelled, in a box on a shelf. It is the only reference this motorcycle will ever have, and keeping it costs nothing. Anyone hoping to judge the result should also be changing one thing at a time, which this kit by its nature will not allow.

What the higher flow figure is, and what it is not

Fifteen thousand litres per square metre per second describes a steady stream crossing clean cloth on a test bench. It is a ceiling rather than a delivery — an engine draws what its throttle bodies, valve timing and displacement allow, and a coarser weave does not lift that limit. What the figure does describe is headroom, and headroom is spent by sustained wide-open running rather than by road riding. That is who the cloth was drawn for. On a road-registered 675 it will not add power; nothing fitted inside an airbox does. It also asks about two fifths more than the same kit with the standard weave in it.

Care and cleaning

Nothing is added to R135S F1-85-SBK when it is serviced, which is the point of a dry medium. Compressed air applied to the clean side and blown outward is what an ordinary clean consists of. Heavier deposits come away with warm water and a little mild detergent, followed by a rinse until the water runs clear of colour. Drying is passive and unhurried — still or moving air, never a heat source, because heat is what breaks polyester fibre down first. It is refitted dry, with no oil, no spray and no dressing of any kind. The maintenance sheet can be found in the Downloads tab.

Fitment & Compatibility

Made for the airbox of the MV Agusta F3 675 built between 2012 and 2021, once that airbox has been modified to take it. The same number covers the F3 800 of 2012 to 2026 — two machines on the list.