Sprint Filter P08 Air Filter for Road & Track – Honda Grom (2021–2026) SM224S

A model name can hold still while the motorcycle underneath it moves. For 2021 the Grom kept its badge and changed its engine: a reworked 125 single, and a fifth ratio in a gearbox that had managed with four. The hardware feeding that engine was redrawn with it, which is why Sprint Filter lists a separate element for this generation rather than carrying the old one forward. The SM224S is that element — dry woven polyester, cut and framed for the airbox this Grom actually has.

Key Features

• Woven polyester that filters dry, with no oil applied at any stage of its life
• Rated at 80 microns, against a flow figure of 5,050 litres per square metre per second
• Around twice the working area of a typical performance element
• The 22-micron figure belongs to the polyester yarn itself; the openings between threads are a separate measurement
• Goes into the series airbox as it stands — nothing trimmed, no adapter, no fuelling change
• Cleaned and refitted rather than replaced, and covered for two years from the day it is bought

A revision the badge does not mention

What Honda changed in 2021 sits mostly out of sight. The engine was reworked, the gearbox gained a ratio, and the parts that feed the engine were reworked alongside them. Sprint Filter builds an element around a box, never around a name, so when the box changes the catalogue gains a number rather than an extra year on an existing listing. That is the entire reason this part sits beside the earlier one: two shapes for two machines that happen to share a badge. For an owner it is a one-line check — the years on the listing, not the letters on the side panel.

What an element like this is honestly for

It will not make a 125 quicker, and anyone selling it that way is selling something else. A road engine of this size is fed comfortably by its standard intake; the filter was never the thing holding it back. What does change is the shape of the maintenance curve. A paper panel leaves the shop at its best and closes up steadily from there, so the resistance the engine breathes against on the day of a service is not the resistance it breathes against six months later. A woven panel blown clean returns to where it started, again and again, for as long as the motorcycle is on the road. That is a smaller claim than a power figure, and a far easier one to keep.

Care and cleaning

Servicing is dry work. Compressed air is the routine: direct it at the clean face so dirt is pushed back out the way it came in. After a hard season, lukewarm water with a mild detergent does more; rinse until the water runs clear. Then leave it in moving air to dry on its own — no heat gun, no hairdryer, no flame anywhere near it — and refit the SM224S only once it is dry the whole way through. The maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Made for the Honda Grom built from 2021 to 2026. The identical element also covers the MSX125 of those same years, Honda's other name for this machine, so the fitment list shows two entries for a single airbox. Both are set out in the Fitment tab.