Sprint Filter P08 Air Filter for Road & Track – CFMOTO NK 675 (2025–2026) SM290S

The letters NK sit on five different capacities in the CFMOTO listing, and between them they take four different Sprint Filter elements. So settle the identity before anything technical: this page belongs to the 675 of 2025 and 2026, and its housing carries the code SM290S. The 250, 300, 450 and 800 machines are catalogued elsewhere under numbers of their own. A search that stops at the badge finds the right brand and the wrong part, because capacity and model year are what identify an air filter here.

Key Features

• Woven polyester in a single dry layer: 80 µm filtration at a rated 5,050 l/m²/sec
• Retention measured at 93.13 % of 100-micron particles; oiled four-layer cotton reaches 76.42 %
• Dry from first fitting to last, with no coating applied at any point
• Close to twice the filtering surface of an ordinary performance element
• Slots into the standard 675 airbox in place of the paper panel, mapping untouched
• Washed and refitted rather than replaced; two years of warranty from purchase

Capacity first, then the year

CFMOTO reuses its model letters across the range as the range grows, which is sensible for a showroom and unhelpful at a parts counter. Sprint Filter numbers its elements by housing, so the three 2025 machines built around this one — the NK, the SR-R and the SS, all 675 — appear together on this code, while the 450-class NK and SR-S are served by a PM270 number instead. Two checks settle it for good: the capacity on your own machine, then the model year against the list on this page. Get those right and the badge can say whatever it likes.

Why the standard weave is the one for this bike

The P08 is the medium Sprint Filter builds for road and track use, and its balance is the reason. Eighty microns with a rated 5,050 l/m²/sec sits between the fine materials, which hold back more and pass less, and the racing cloth, which does the opposite. On a machine that has to cope with everything a public road offers and still be worth riding on a circuit, the middle of that scale is the point. What no medium in the range does is lift output: a drop-in element will not make a standard NK 675 noticeably stronger. The gain is an intake restriction that returns to its starting value at every service instead of climbing until the next part is bought.

Care and cleaning

Compressed air on the clean face, worked outward across the panel, is the whole of a normal service — what the cloth stopped leaves by the way it came in. A greasy film rather than dry dust calls for lukewarm water and a little mild detergent, rinsed until it runs clear. Then air and time do the rest: no heat gun, no radiator, no flame, and nothing goes back into the box damp or treated with anything. Sprint Filter's maintenance sheet for the SM290S is in the Downloads tab on this page.

Fitment & Compatibility

Cut for the airbox of the CFMOTO NK 675 as built in 2025 and 2026, one element per machine. Three CFMOTO 675 models share this part number; the smaller and larger NKs do not. The complete list is in the Fitment tab.