Sprint Filter P08 Air Filter for Road & Track – Yamaha MX King (2015–2026) PM186S

Service intervals are written in kilometres because kilometres are easy to count, but a filter does not age by distance. It ages by the volume of air that has gone through it, and that is a function of running time and load rather than of the number on the odometer. A small machine that spends its life at modest average speeds accumulates a great many running hours per hundred kilometres travelled. Two MX Kings showing the same reading can therefore hold elements in entirely different condition. The Sprint Filter P08 PM186S is the answer to that mismatch: an element you can pull out and inspect whenever the riding suggests it, rather than one you replace when a table says so.

Key Features

• Dry P08 polyester: washed and refitted where a paper element would be discarded
• Filters at 80 microns and flows 5,050 litres per square metre per second
• Filtering surface roughly twice that of other performance filters
• No oil anywhere in the medium, so the throttle body and the intake sensors stay clear of it
• Original airbox, original map — the element is the only thing that changes
• Two years of warranty, dated from purchase

The odometer under-reports

An engine running at low road speed is still turning, still drawing its full share of air on every intake stroke, and still filtering everything that comes with it — but the wheel is covering very little ground while it happens. Slow running has a second consequence: there is little airflow past the machine to carry heat away, so the whole area around the engine sits warmer than it would at speed. Neither effect harms a dry polyester element, which has no oil to thin and no binder to soften, but both are good reasons to judge the filter by looking at it rather than by arithmetic.

An inspection that costs nothing

With a paper filter, taking a look is a decision with a price attached — if it turns out to be dirty, a new part has to be bought, so the temptation is to leave it until the service is due anyway. With the PM186S the same check ends with compressed air and a refit. That changes the economics of curiosity, and it is the whole honest case for the part: not more power, which an element in a standard airbox cannot deliver, but an intake whose condition is actually known instead of assumed, and a resistance figure that stays where it started.

Care and cleaning

Compressed air does the work on the PM186S: clean side first, blown outwards. When the element has taken on more than air will shift, wash it in lukewarm water with a mild detergent and rinse until the water runs clear. It then dries fully in open air, away from any heat and any flame, and goes back in dry. No oiling closes the job, because the polyester has never been oiled. The Sprint Filter maintenance sheet sits in the Downloads tab.

Fitment & Compatibility

Made for the Yamaha MX King, 2015 to 2026, and a direct replacement in the standard airbox. The same PM186S element is listed for six model names across that period; the full list is in the Fitment tab.