Sprint Filter P08 F1-85 Air Filter for Racing – Triumph Rocket III (2004–2018) CM232S F1-85

Sprint Filter specifies its elements for the life of the motorcycle. On a machine built between 2004 and 2018, that promise deserves a careful reading, because the interesting horizon is no longer the motorcycle's life — it is yours with it. A Rocket III bought now will likely be kept for a defined run of seasons and then passed on. A part that outlives the ownership is not wasted, but it does change what the purchase is: less an investment in the machine's distant future, more a specification you set for your own years and hand over intact.

Key Features

• Racing specification in dry polyester: rated 85 µm, flowing 15,000 l/m²/sec
• Flow roughly trebled against the series element, on a slightly more open weave
• Retention measured at 95.22 % on 100-micron particles; the P08 returns 93.13 %
• Used without oil of any kind, so there is no film that could travel further in
• Original airbox, original position, no housing modification and no remap
• Two years' warranty from purchase, at a little over twice the price of the P08

A lifetime part on a machine with a known past

The element will still be serviceable when the bike changes hands, and whoever buys it next inherits a specification they did not choose and will not find in any paperwork. That is worth being deliberate about. Keep the original panel filter, labelled, so the motorcycle can be put back to standard; write the medium and the date somewhere the next person will actually look. None of this argues against fitting a racing element. It argues for treating the fitting as a documented change rather than a quiet one.

What the more open weave swaps away

Air passes more freely and fine material is stopped less thoroughly: those two sentences are the same sentence. The F1-85 is not a better P08, it is the same dial turned towards supply and away from filtration, and there is no setting of that dial that gives both. Sprint Filter names the paddocks of World Superbike, Supersport, Superstock, Moto3 and MotoGP as the home of this class of medium — the maker's own account of where its product is used, not an outside audit, and in any case a statement about racing rather than advice for a road-going cruiser. On a standard Rocket III the element adds no power. Nothing sitting in an untouched airbox does.

Care and cleaning

Blow it through from the inner face, so that whatever the weave held is pushed back towards the dirty side and out. When air alone leaves the pleats grey, wash it in lukewarm water with a small amount of mild detergent, then rinse until nothing more comes away. Drying is the step that gets people into trouble: leave it in moving air until it is dry the whole way through, keep it clear of radiators, hot air guns and naked flames, and put it back untreated. The service sheet for the CM232S F1-85 sits in the Downloads tab.

Fitment & Compatibility

The F1-85 element for the Triumph Rocket III, model years 2004 to 2018. The same standard airbox takes the P08 and the fine P14, so a return to road specification costs nothing beyond the element itself.