Sprint Filter P08 F1-85 Air Filter for Racing – Honda CB650R (2019–2026) PM201S F1-85

Fifteen thousand litres per square metre per second is a big number, and on a 650 four not a silly one to want: this short-stroke inline four does its real work at the top of the rev range, where a medium's flow rating begins to matter. The catch on a CB650R is that the capacity is only claimed while the engine is up there — and on a naked bike what ends that run is the rider in the wind, not the engine. The CB visits the rev range this medium was written for. It does not live there.

Key Features

• Dry polyester, run with no oil at all — nothing to re-treat, nothing to carry onto a sensor
• Sprint Filter's racing weave: 85 µm at 15,000 l/m²/sec, close to triple the flow of the P08
• Five microns coarser than the P08's 80 — a step back in filtration, paid for with flow
• Area is not the scarce thing: about twice the cloth of a usual performance element
• Takes the paper panel's place in the series airbox, with ducting and mapping left alone
• Cleaned and refitted rather than consumed, with two years of Sprint Filter cover

Where the flow gets claimed, and where it goes unused

A flow rating is a ceiling, not a delivery: the engine draws what it draws. Below the top of the rev band the standard P08 has plenty in hand: 5,050 l/m²/sec is more than a 650 asks at road speeds. The media only differ where the engine is held near maximum airflow for a sustained spell, and holding a naked CB650R there is physical work: wind pressure on an upright rider ends the run long before the motor would. Behind a fairing it lasts a whole straight, lap after lap — and that difference in bodywork is nearly the whole difference here.

When the coarser weave is right, and when it is not

Plainly: 85 µm passes a band of particles that 80 µm holds, every hour the engine runs, and the debt is settled on bores and valve seats, not on a dyno sheet. A race programme can carry it, because it counts service in running hours rather than kilometres and opens the engine on a schedule of its own. A road-ridden CB650R has no such accounting: it takes the coarser filtration through commuting, wet weeks and winter grit and never spends the flow it bought. It is also one of the dearer elements here, and on a road naked that money buys idle capacity. For the street the P08 (80 µm, 5,050 l/m²/sec) is the sane choice; where dust is the problem the P14 (14 µm, 1,800 l/m²/sec) trades the other way — one trade, not a ranking.

Care and cleaning

A racing medium wants looking at more often, and the PM201S F1-85 makes that cheap: inspected, not reordered. Work from the clean side with compressed air so the dust leaves the way it came in. After a wet session, lukewarm water with a mild detergent lifts what air will not; rinse until clear. Dry it in open air, never near a heat gun, radiator or flame, and refit it bone dry and untreated. The maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Cut for the airbox of the Honda CB650R, 2019 to 2026. Two machines are covered: this one and the faired CBR650R of the same years. Both are listed under the Fitment tab.