Bad day bonus: Silca believes its new tubeless sealant is so good, it will pay athletes $500 when they flat

There’s no way around it – tubeless tyre sealant is messy. It spills easily, spurts out of the valves or seating bead, and sticks to everything. But it’s also worth it, saving you from annoying flats or mid-race, time-costly punctures.

When it works, there’s that split-second oh sh$t moment as you spot the puncture—then relief floods in as the bubbling sealant gets to work before you lose your momentum. But if it fails, you’re either cursing on the side of the road, messily inserting a spare tube or calling for a ride.

Silca aims to relieve tubeless headaches with its new Ultimate Sealant with Injectable FiberFoam. The formerly Italian, now American, brand has made it a mission to take everyday cycling products and improve them. From aero socks to pumps and chain waxing equipment, its product line runs the gamut. Its original Ultimate Sealant was well-used among the Cycling Weekly staff, and the top performer in our ‘best tubeless sealant’ test thanks to its quick sealing properties, longevity and cold weather performance.

Silca’s new Ultimate Sealant with Injectable FiberFoam isn’t just a tweak on this already high-performing formula—it’s a full evolution.

“The two downsides of the original design were that it had to be poured into the tyre as it could not be injected through the valve, and the 100% natural latex formula needed to be replenished with a separate replenisher product to keep the sealant liquid,” Silca explains.

So, the brand’s engineers went back to the drawing board, spending the past two and a half years devising and testing new formulas. The result is a blend of natural and synthetic latex combined with a new—and importantly, injectable—FiberFoam that uses single-strand carbon fibres as an occluding agent.

Silca promises a longevity of more than six months—even in hot climates—and a sealing ability for punctures measuring 6mm+ without clumping.

“Historically, the two main goals of a sealant were to seal and last long. Those two properties have been mutually exclusive. You typically cannot target one without affecting the other. Our first-of-its-kind natural and synthetic latex blend bridges that gap to create a product that really has the best of both worlds," says Richard Pool, Marketing Director at Silca.

Now, we haven’t sliced open any tyres yet to put this claim to the test, nor have we had the new sealant long enough to assess its longevity. But Silca is so confident in its new product that it’ll be paying its sponsored gravel racers a $500 “bad day bonus” if the sealant fails to seal a flat during a Life Time Grand Prix event this season.

Is this the holy grail of sealants? Only time—and enough miles—will tell. But the fact that Silca is willing to bet against its own failure makes this a product worth paying attention to.

The Silca Ultimate Sealant is now available online and at select bike shops.

Pricing:

- $/£42.00 for 1L

- $/£24 for 0.5L,

- and $/£6 per 65ml