{"product_id":"sprint-filter-p08-f1-85-air-filter-royal-enfield-goan-classic-350","title":"Sprint Filter P08 F1-85 Air Filter for Racing – Royal Enfield Goan Classic 350 (2025–2026) CM231S F1-85","description":"\u003cp\u003eThe word Racing in this title came from the filter, not from the motorcycle. Sprint Filter attaches it to the F1-85 medium wherever that medium appears in its catalogue, and the catalogue happens to list the CM231S F1-85 for the Goan Classic 350 airbox. Nothing in that arrangement says a Goan Classic is a race bike, and nothing about fitting the element makes it one. Reading a medium label as a description of the machine underneath it is the most common way to end up with the wrong filter, so the two are worth separating before anything else.\u003c\/p\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eThe racing medium from the Sprint Filter range: dry polyester, 85 µm, 15,000 l\/m²\/sec\u003c\/li\u003e\n\u003cli\u003eBy Sprint Filter's own account the most used air filter in MotoGP, Moto3, World Superbike, Supersport and Superstock\u003c\/li\u003e\n\u003cli\u003eRetains 95.22 % of 100-micron particles in the manufacturer comparison\u003c\/li\u003e\n\u003cli\u003eNo oil in service, so nothing can be over-applied and nothing can travel forward\u003c\/li\u003e\n\u003cli\u003eRoughly twice the filtering surface of other performance elements, in the series housing\u003c\/li\u003e\n\u003cli\u003eDirect replacement in the standard airbox with no remap; two years of warranty\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWhat the paddock record does and does not transfer\u003c\/h2\u003e\u003cp\u003eThe claim in the list above is the manufacturer's, not an independent measurement, and even taken at face value it describes engines that share very little with a 350 cc single. What travels from a grid to a road bike is the fabric and the way it is made. What does not travel is the context around it: sessions measured in minutes, engines stripped between them, and intake systems reworked to the point where the filter is genuinely part of the limit.\u003c\/p\u003e\u003ch2\u003eThe Goan Classic case, plainly\u003c\/h2\u003e\u003cp\u003eThis machine reaches its owner with a standard airbox, standard fuelling and a service interval counted in kilometres. Against that, the element asks a little over three times what the standard filter for the same box asks, and returns a coarser rating in exchange for flow the engine will never call on. It adds nothing to output either, because a drop-in filter does not make a standard 350 single noticeably stronger. The standard medium is the better purchase here by a wide margin.\u003c\/p\u003e\u003ch2\u003eCare and cleaning\u003c\/h2\u003e\u003cp\u003eThe routine is dry and short: compressed air on the clean face, worked outwards through the weave, then straight back into the box. Anything oily that air leaves behind comes out with lukewarm water and a mild washing-up liquid, rinsed clear. Let it dry in open air and nowhere near heat or flame, then refit it untreated. The CM231S F1-85 maintenance sheet is in the Downloads tab.\u003c\/p\u003e\u003ch2\u003eFitment \u0026amp; Compatibility\u003c\/h2\u003e\u003cp\u003eCatalogued for the Royal Enfield Goan Classic 350 in 2025 and 2026. The same element serves five bikes in this family: besides this one, the Bullet 350, the Classic 350, the Hunter 350 and the Meteor 350. Model years are set out under Fitment.\u003c\/p\u003e","brand":"Sprint Filter","offers":[{"title":"Default Title","offer_id":53533954507018,"sku":"CM231S F1-85","price":8573.0,"currency_code":"THB","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7831\/0410\/files\/CM231S-F1-85_71ddf50c-ece2-4534-bea3-62a33ab58194.png?v=1787146968","url":"https:\/\/inter-pace.com\/en-th\/products\/sprint-filter-p08-f1-85-air-filter-royal-enfield-goan-classic-350","provider":"Inter-Pace","version":"1.0","type":"link"}