Sprint Filter P08 F1-85 Air Filter for Racing – Yamaha MT 15 /MT 155 (2018–2026) PM198S F1-85

A flow figure is a statement about capability, not about consumption, and on a single-cylinder engine the difference between those two matters more than usual. A single draws air in one large event every second revolution rather than in the overlapping succession of a multi-cylinder engine, so what the intake has to satisfy is a series of peaks with gaps between them. The average is modest; the peak is not. That is the number an element has to be dimensioned against, and it is why the P08 F1-85's 15,000 l/m²/sec — against the standard P08's 5,050 — describes headroom rather than a promise.

Key Features

• 15,000 l/m²/sec — the highest air flow Sprint Filter offers, and the racing medium's reason for existing
• Filtration to 85 microns: a coarser weave than the road medium, chosen deliberately
• Polyester used dry, never oiled, so nothing can migrate onto the throttle body or sensors
• A direct replacement in the standard airbox — no modification, no remap
• A filtering surface roughly twice the size of other performance filters'
• Washable and reusable, serviced with compressed air from the clean side

Headroom the standard engine already has

The honest consequence is that a standard MT 15 is not short of intake capability, even at its peaks. The standard P08 already provides more than a 155 cc single asks for, which means moving to the racing medium does not release anything — it simply exchanges filtration for capacity that is not being used. The exchange is real in one direction only: 85 microns against 80 is a coarser barrier, on a machine that is likely to be kept and ridden on public roads for years.

The condition that changes the answer

Once the intake path has been opened up, the exhaust changed and the fuelling adjusted, the peaks rise and the calculation moves. An engine prepared that way and maintained on a racing schedule can use what the F1-85 delivers, and the coarser weave becomes a decision taken with the maintenance to support it. Short of that, the choice on this platform is between the standard P08 for general road use and the P14 at 14 microns where the air is dusty — and the airbox accepts any of them without modification. The one thing that does not change with the fabric is the shape of the argument: a finer weave holds back more and passes less, always, and the range is a line rather than a ladder. Across the three media that reads 85 microns at 15,000 l/m²/sec, 80 at 5,050, and 14 at 1,800.

Care and cleaning

Compressed air over the clean side of the PM198S F1-85, directed outwards, and refit it dry. Where a deeper clean is due, lukewarm water and a mild detergent will do it; rinse until the water runs clear, then dry fully in air, never with heat and never with a flame. It is never oiled. The Sprint Filter maintenance sheet is kept in the Downloads tab.

Fitment & Compatibility

Made for the Yamaha MT 15 and MT 155 from 2018 to 2026. The same PM198S F1-85 element covers seven machines across the 125 and 155 range; the complete list is in the Fitment tab.