Introducing Silca Ultimate Tubeless Sealant
15 March 2022
By Rob Borek
Silca may be new on the scene when it comes to tubeless sealant, but a thoroughly researched approach has helped them to conceive what we are expecting to be one of the highest performing sealants available.
In testing the offerings of market leaders Silca have found that one of the main issues preventing sealants from working more effectively is that the small particles and additives commonly used to plug holes need to be mobile to reach the puncture area.
When a wheel is spinning and acting as a centrifuge, the particles in most sealants can't get to where they are needed, especially in the case of a sidewall puncture. It’s no good your sealant being full of sand, glitter, walnut shells, or whatever else if those hole-plugging additives can’t get where they need to be.
The solution to this is to use an additive with a low density and high surface area suspended in a foaming solution. This helps the additive get to where its neeeded, and to seal the puncture quickly and effectively.
Low Density Additive
In the search for a low density additive Silca have settled on recycled carbon fibre strands, with CEO Josh Poertner telling us that initial prototypes were made from the body of a crashed Corvette C5R race car. These recycled fibres are 400% stiffer than glass fibres, and achieve better dispersion in the sealant for faster sealing with less air loss.
Silca assures us that the environmental impact of this material is extremely minimal. In the recycling process the carbon is ‘unsized’ which means that it is reduced to carbon fibre in its raw form. With no epoxy resin bonding it together it’s not unlike the activated charcoal used in water filters. Sure, as with any sealant you don’t want to pour it out into the environment if you can help it, but it does not contain any volatile ingredients, and won't be harmful to the environment if an incident results in a spillage.
They have found the carbon strands to act in combination with a foaming latex solution to form a structural dam against the tyre casing, resulting in a high strength repair which will allow the tyre to hold a high pressure without leaking from the punctured area as some other sealants do. In testing Silca have found their Ultimate FiberFoam® Sealant to work at up to 90 PSI in road tyres.
The puncture sealing effectiveness of Ultimate sealant is such that it cannot be installed through the valve stem and will seal the 8mm hole in many syringes. This means that the sealant needs to be poured directly into the tyre on installation. We’re sure you will agree this is a worthwhile trade off in short term convenience for the puncture sealing performance it provides.
Once your tyre is set up with Silca Ultimate Tubeless Sealant, it can be topped up using their Ultimate Replenisher, which is a version of the sealant with no carbon fibre additive and a higher percentage of anti-freeze. This makes up for any sealant loss through evaporation and can extend the life of your sealant to up to 1 year depending on your local conditions and climate. Unlike the sealant itself the replenisher can be installed through the valve if required.
