Sprint Filter P08 F1-85 Air Filter for Racing – Honda CMX500 Rebel (2017–2026) PM241S F1-85

This housing serves two motorcycles, but not with the same choice of cloth. Sprint Filter lists the standard weave and the 14 µm dust medium against both the CMX300 and the CMX500 Rebel; the racing specification, PM241S F1-85, is recorded against the 500 alone. That asymmetry is worth reading correctly, because it is easy to read as a recommendation. It is not one. A catalogue entry records where a part has been listed, and a gap in a list is not a technical verdict — it is simply the absence of an entry.

Key Features

• P08 F1-85 racing weave: 85 µm filtration at a rated 15,000 l/m²/sec
• Dry polyester throughout, never oiled, so nothing migrates down the intake
• Deep pleating fits far more cloth into the same standard airbox volume
• Goes into the original CMX500 housing unaltered, with no remapping
• Serviced with compressed air and refitted rather than thrown away
• Rated for the life of the motorcycle; two years of guarantee from purchase

What a gap in a list means

Listings are built from housings and from demand, and both move over time. The safe conclusion from this one is narrow: if you have a CMX500, this reference is recorded for your machine and the fitment is documented. If you have the smaller Rebel, it is not, and the entries that are recorded for it are the standard element and the finer PM241P14. Nothing here should be extrapolated in either direction — not that the racing cloth is unsuitable for the 300, and not that it is particularly suited to the 500. The listing states coverage, and that is all it states.

What is actually being chosen

The specification is the part worth reading. Against the standard element in the same housing at 80 µm and 5,050 l/m²/sec, the racing weave is rated at 85 µm and 15,000 — coarser and much faster, which is one exchange rather than an improvement. It costs around three times the standard cloth for this box, and it is a lifetime part, so the exchange stays in force for as long as the bike is kept. On a road-registered mid-capacity cruiser the flow is rarely called upon, while the aperture applies every hour. The honest recommendation for most owners is the standard PM241S; no element makes a standard Rebel stronger, and this one is sold on flow, not on power.

Care and cleaning

Regeneration is dry work throughout. Compressed air on the clean face of PM241S F1-85, blowing outward, moves most of the load back out the way it came. Where more is needed, hand-warm water with a mild detergent will finish it; rinse until clear and dry it in still air. Heat guns, exhausts and flames are off limits, and it goes back into the airbox dry and untreated. The Sprint Filter maintenance sheet is in the Downloads tab.

Fitment & Compatibility

PM241S F1-85 is recorded against one machine: the Honda CMX500 Rebel from 2017 to 2026. The same housing also takes the standard PM241S and the finer PM241P14, both of which additionally cover the CMX300 Rebel. Check your model and build year against the compatibility list on this page before ordering.