Sprint Filter P08 F1-85 Air Filter for Racing – Yamaha MT 125 (2021–2026) PM198S F1-85

The MT 125 and the YZF-R125 share an engine, an airbox and this element, and they lead entirely different lives. One of them has a place in junior racing; the other is a naked A1-class bike that commutes, learns and carries its rider to college. That distinction decides whether the P08 F1-85 makes sense here, because the racing medium is the only fabric in the Sprint Filter range that filters more coarsely than the standard one — 85 microns against the P08's 80 — and it buys about three times the air flow with that difference: 15,000 l/m²/sec against 5,050.

Key Features

• The P08 F1-85 racing medium, and the highest air flow Sprint Filter lists: 15,000 l/m²/sec
• Filtration to 85 microns — a wider aperture than the road medium, and deliberately so
• Polyester used dry, with no oil to travel onto the throttle body or the sensors
• Goes into the standard airbox in place of the original — nothing modified, no remap
• Washable and reusable; the entire service is compressed air from the clean side
• Two years of warranty, on an element made to last the life of the motorcycle

An A1 engine has no use for that much air

A 125 built to a legal power ceiling is not an engine held back by its intake. It is held back on purpose, by mapping and by the way it is built, and no filter changes that. Fitting the F1-85 to a standard MT 125 therefore trades a small amount of filtration for flow the engine will never draw, which is a bad exchange dressed up as an upgrade. The standard P08 is the right element for this bike, and the P14 at 14 microns is the right one if the roads it uses are dusty. It is worth being specific about what a filter can ever return, on any motorcycle: the restriction it was adding, and nothing more. On a healthy standard intake that quantity is small, which is why no bolt-in element makes a standard machine noticeably quicker and why anyone promising otherwise is describing something else.

Where it does belong on this platform

The exception is real and worth stating. Some of these engines end up in machines that race, and some owners work through the intake and exhaust and have the mapping adjusted to match. At that point the engine can act on what arrives, the maintenance moves to a schedule counted in running hours rather than kilometres, and the coarser weave becomes a considered decision instead of an overlooked one. The PM198S F1-85 is the part for that stage.

Care and cleaning

Compressed air across the clean side of the PM198S F1-85, worked outwards, then refitted dry. A deeper clean means lukewarm water with a mild detergent, rinsing until the water runs clear, and full drying in air — never with heat, never near a flame. There is no oil on it before a wash and none after one. The Sprint Filter maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Made for the Yamaha MT 125 from 2021 to 2026. The same PM198S F1-85 element covers seven machines across Yamaha's 125 and 155 range; the complete list is in the Fitment tab.