Review: Finish Line Tubeless Tyre Sealant

With tubeless tyres becoming more and more mainstream the number of sealant options is also increasing. Here Peter Maniaty reviews the latest from Finish Line.

Currently, the vast majority of tyre sealants are latex-based, but one that takes a curiously different approach is Finish Line Tubeless Tyre Sealant. Rather than latex, which typically requires ammonia to stop it from coagulating inside your tyre, Finish Line uses an entirely non-toxic water-based fluid that carries thousands of DuPont Kevlar microfibres—known as FiberLink seals—to repair any breaches to a compromised tyre.

Tubeless tyres are particularly popular in gravel cycling, an area of the sport that has boomed in recent times.

…At first glance this stuff looks more like a choc-chip thickshake than tyre sealant, filled with tiny black dots suspended in an otherwise white liquid…

ABOVE: Rather than the typical Latex approach, this tubeless sealant from Finish Line features small Kevlar fibres to help block and seal punctures.

At first glance, this stuff looks more like a choc-chip thickshake than tyre sealant, filled with tiny black dots suspended in an otherwise white liquid. The consistency is notably more viscous than latex sealants, something that certainly makes it a little trickier to inject cleanly into the tyre at first, especially through standard diameter tubeless valves.

How does it work?

When a puncture occurs, the escaping air forces the Kevlar fibres directly into the breach. Then, as the tyre flexes while it’s ridden, the FiberLink seals continually tighten and reinforce themselves, creating a robust and long-lasting seal that minimises air loss and negates the need for roadside repairs or tube replacement. (I’ve only been riding with it for a few hundred km’s to date, so will report back on real-world efficacy a little in later
in the year).

Unlike liquid latex, which generally degrades and dries out over time, Finish Line Tubeless Tyre Sealant rarely needs to be replenished. In fact, depending on the porosity of the tyre, Finish Line claims one application of sealant is often enough to last the entire usable life of the tyre. It won’t dry out in the bottle either, meaning longer shelf life and the ability to save money by buying in larger volumes (a good thing, given it’s roughly double the price of the leading latex-based sealant).

Unlike the warnings from some sealant manufacturers, there are also no issues with using CO2 cartridges. One other common complaint of latex sealants is the gawd-awful mess should you ever suffer a large and/or explosive puncture. Finish Line Tubeless Tyre Sealant cleans up easily with water, meaning no more scrubbing or scraping cured latex from your tyres, frame or rims.

Oh, and one final point. Finish Line Tubeless Tyre Sealant is often known to turn blue over time. Finish Line explains this is an entirely cosmetic reaction when it comes into contact with the rubber in some tyres and has zero impact on performance … so stay calm and ride on.

RRP: $74.99 (1 litre)
RRP: $29.99 (240mL)