Sprint Filter P08 Air Filter for Road & Track – BMW R 1250 GS (2019–2023) PM142S

The 1250 boxer arrived in 2019 with a variable intake camshaft. BMW gave the inlet valves two profiles, a mild one for part load and a full one for everything else, and let the engine switch between them as it runs. That is substantial work on the intake side of the motor. What BMW did not change is the box in front of it — Sprint Filter's catalogue carries one element across the 1200 and the 1250 alike, which is a quiet confirmation of where the new engineering stopped. The PM142S therefore has to suit two rather different appetites for air with a single piece of cloth.

Key Features

• Dry woven polyester in a single layer, never oiled and never treated after cleaning
• 80 µm aperture and 5,050 l/m²/sec of rated flow, the road and track specification of the P08
• Polyester threads from ø 22 microns in diameter; the mesh they form is the larger figure
• Roughly twice the filtering area of other performance filters, carried in the original frame
• A direct exchange for the factory panel — the housing is not altered and no remap is needed
• Washable and reusable for as long as the motorcycle runs, with a two-year guarantee

One element, two intake regimes

Part load and full load are not small variations on each other. In the first the engine is throttled, drawing modestly and often; in the second it takes all the box will give. The filter serves both from one fixed area, which is why the medium's behaviour over time counts for more than its figure on the day it was fitted. A woven element is returned to its starting resistance by cleaning. A paper panel only ever moves in one direction, and the moment its restriction starts to matter is not announced. None of that is a power claim. The honest limit is that this element gives a standard boxer no noticeable extra power, because the intake was designed with a filter in it.

Nothing applied, nothing carried downstream

Behind the panel sit the intake sensors and electronically managed throttles, both good reasons to keep oil out of the tract. The P08 is dry when it arrives and stays dry through every wash, so there is no film for the airstream to pick up and deposit further in. Being dry costs nothing in retention either: in Sprint Filter's comparison the P08 held 93.13 per cent of 100-micron test particles where four-layer oiled cotton managed 76.42 per cent.

Care and cleaning

An air line is the whole of the routine: clean side to the nozzle, blowing outward, until the weave runs clear again. Where a gravel week or a salted winter leaves a residue, tepid water and a mild detergent will remove it; rinse until the water runs clear. Drying is done in open air and by nothing else, since heat is what destroys polyester — keep it away from heat guns, radiators and flame. Refit it dry. The maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Made for the BMW R 1250 GS of 2019 to 2023, replacing the standard paper element in the unmodified airbox. Nine machines in total are covered by this part number, spanning both boxer generations; the list is in the Fitment tab.