Sprint Filter T12 Air Filter for Off-Road & Extreme – Honda CRF450RX (2021–2026) SM248T12

Desert and open country is the terrain the T12 was specified for, and the CRF450RX is the machine in this family most likely to be out in it — sand washes, dry open trail, long stages where the air never really clears. That environment is not simply dustier than a motocross track; the dust in it is different. The grit a wheel throws up falls back down within seconds. What stays in the air over open ground is the fine mineral fraction, and that is the fraction an engine actually inhales. The Sprint Filter T12 SM248T12 filters to 7 microns.

Key Features

• Cleaned with compressed air instead of replaced, which is what makes it reusable at all
• A dry polyester special non-woven at 7 microns, aimed at desert, open off-road and extreme conditions
• Rated flow of 560 l/m²/sec — flow traded for retention, deliberately
• No oil at any stage, so nothing can be pulled downstream into the intake
• The standard airbox takes it directly: no modification, no remap
• Backed for two years, starting the day it is bought

The dust that stays up is the dust that gets in

Airborne mineral dust sorts itself by size within moments of being disturbed. The coarse material is heavy enough to drop out of the air almost immediately; the fine material hangs, drifts sideways with the wind and is still there long after the rider who raised it has gone. An intake tract on open ground therefore sees a diet weighted heavily towards the small end, which is exactly the material a coarse weave lets through. That is the argument for the numbers here: 80 microns on the P08 and 14 on the P14 against 7 on the T12, with flow falling from 5,050 to 1,800 to 560 l/m²/sec as retention rises. It is a trade in both directions, and on sand and desert ground it happens to fall on this side of the line.

One element, two very different jobs

The same part number serves the R and the RX, the 250 and the 450 — the element is catalogued by the airbox it sits in, not by the discipline the machine is raced in. On an RX ridden across open terrain and sand the fine weave earns its restriction several times over. On a prepared, watered circuit the same element is the wrong end of the trade, and the P08 or the F1-85 gives the engine more of the air it is asking for. Nothing about the fit changes either way: the SM248T12 goes into the standard airbox as the original element does, with no adaptation, no repositioning and no mapping work.

Care and cleaning

The dust comes out the way it went in: compressed air on the clean side, blown outwards. Sand that has turned to grime needs water — lukewarm, with a mild detergent, rinsed until the water runs clear — and then a long spell in open air, because the medium will not survive heat or a flame. It goes back into the airbox dry and unoiled, exactly as it came out of the box. The maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Made for the Honda CRF450RX from 2021 to 2026. The same element covers four machines in the CRF competition range; the complete list is in the Fitment tab.