Sprint Filter P08 F1-85 Air Filter for Racing – Zontes ZT 350-V (2020–2026) SM277S F1-85

There is a far larger restriction in this intake than any filter, and the rider operates it with his right hand. A throttle plate a quarter open is a tighter constriction than any air filter ever built, which is why the medium in the airbox only becomes a measurable share of the total once the throttle is out of the way.

Key Features

• Racing medium: dry polyester filtering at 85 µm, rated at 15,000 l/m²/sec of flow
• A capacity figure, not a delivery figure — it describes what the material can pass under test
• The standard element for this housing is rated 80 µm at 5,050 l/m²/sec and costs far less
• Dry throughout, never oiled, so nothing migrates onto the throttle body or the sensors behind it
• Direct exchange for the series panel; the airbox and the mapping are untouched
• Roughly twice the area of an ordinary performance element, cleaned and reused, two years of warranty

Where a filter medium is even visible

Restriction accumulates along the intake, but the terms are wildly unequal and they shift with throttle position. At small openings the plate dominates so thoroughly that changing media alters almost nothing anywhere behind it. The element's share climbs only as the throttle approaches fully open with the engine drawing hard — and on a road-registered 350 that is a thin slice of any year, arriving a few seconds at a time, at speeds most roads do not invite. A medium rated at 15,000 l/m²/sec is specified for machines that live inside that slice rather than visiting it.

The half of the trade that never switches off

The weave has no operating condition. Whatever an 85 µm cloth passes, it passes while idling in traffic, while cruising at a steady speed, and during the one full-throttle exit of the afternoon alike. That asymmetry is the honest core of the decision: the benefit is occasional, the cost is continuous. The cost is not large — retention on 100-micron dust is measured at 95.22 %, ahead of the standard element's 93.13 %, and the fine fraction is where neither figure reaches — but it is paid every minute the engine turns, and no slot-in element makes a standard motorcycle faster to begin with. For a ZT 350-V the standard specification asks a great deal less for capacity that is genuinely usable.

Care and cleaning

Hold compressed air to the clean side and blow outward through the material; the load then leaves by the route it entered. Greasy deposits need lukewarm water and a mild detergent, and the rinse continues until the water runs off clean. From there the drying is done by circulating air at ambient temperature only, never by a heat gun, an oven or a flame, and the SM277S F1-85 is refitted dry and bare. Sprint Filter's maintenance sheet can be found under the Downloads tab.

Fitment & Compatibility

The racing element for the Zontes ZT 350-V, catalogued 2020 to 2026. Eight further Zontes machines sit behind the same code across three capacity classes. Match the code first and the build year second.