Racing Flat Guard

Several major sealant brands rely on aramid fibres, Kevlar fibres or recycled rubber crumb to plug holes, materials that don't biodegrade, even when the product is marketed as eco-friendly. Racing Flat Guard uses a bio-latex base with cork particles instead, no microplastics, no rubber crumb.

Independent testing shows plenty of sealants inconsistently fail on medium-sized punctures, in the 3 to 4mm range, even when they're expected to hold. Racing Flat Guard's cork particles are sized to fill a puncture properly on the first pass, built specifically for the pressures road tyres run at.

Any sealant adds some weight, roughly 50 grams of liquid per tyre is normal regardless of brand. Where Racing Flat Guard makes the difference is the filler itself: its cork particles are on average 15% lighter than particles used in existing sealant formulas, so within that same 50 grams, less of the weight comes from dead filler and more of the tyre's rolling feel stays unaffected.

Valve clogging is a common complaint, typically from fibrous or rubber additives building up inside the valve core over repeated top-ups. Racing Flat Guard's cork particles work on a different principle than those fillers, though as with any sealant, keeping the valve clean during top-ups stays good practice.