Sprint Filter P08 Air Filter for Road & Track – BMW R 18 (2020–2026) PM246S

An element is drawn around a housing, not around a displacement, and almost every part number in this catalogue serves a family: one airbox shared by four or five machines with different engines and appetites. PM246S serves exactly one motorcycle. The R 18 has its own housing, its own part number and a fitment list one line long, which means the panel inside it was specified against a single engine's requirement rather than against the busiest case in a range.

Key Features

• A single woven polyester layer, dry from new and dry again after every wash
• The P08 specification: 80 µm aperture, rated 5,050 l/m²/sec, for road and track use
• Threads from ø 22 microns across; what filters is the opening between them
• Roughly twice the filtering cloth of a typical performance element, in the original frame
• Replaces the paper panel in the standard airbox with nothing cut and no remapping
• Cleaned and refitted for the life of the machine, with a two-year warranty

One machine, one specification

The large twin in the R 18 does its work low in the rev range and is geared and mapped to be used there, which is a very different demand pattern from a supersport four sharing its airbox with three other models. A part drawn for a single machine can sit exactly where that machine needs it to sit. It also simplifies ordering: there is no year split to check, no variant that quietly took a different housing, and no chance of buying the right name on the wrong intake. Three media are catalogued for this one motorcycle, and the standard weave is the default among them.

What it changes and what it does not

Sprint Filter's own comparison puts this dry weave at 93.13 per cent retention of 100-micron test particles against 76.42 per cent for four-layer oiled cotton, and it reaches that without any oil at all: nothing to reapply after a wash and nothing to travel downstream. What it does not do is add power. A panel inside an unmodified airbox cannot, on this engine or on any other, and an R 18 is not a machine bought for peak figures in the first place. The real change is that intake restriction returns to the same value after each clean instead of climbing slowly until a service throws the paper away.

Care and cleaning

PM246S is a bench job rather than a roadside one, and a simple one: compressed air on the clean face, blowing outward, until the weave is clear. Where the deposit has turned greasy — usually a summer of insects rather than dust — hand-warm water with mild detergent takes it off, rinsed until clear. Dry it in moving air alone, with no heat gun, no radiator and no flame anywhere near it, since heat is what destroys polyester, then refit it dry and unoiled. The maintenance sheet is under the Downloads tab.

Fitment & Compatibility

For the BMW R 18 built from 2020 to 2026, as a direct replacement in the series airbox. The fitment list holds this machine alone. Two further media are catalogued for the same housing: the 14-micron PM246P14 for dusty roads and the racing PM246S F1-85. The Fitment tab shows the year span.