Review: Silca Ultimate Tubeless Sealant Replenisher

Silca Ultimate Tubeless Sealant Replenisher is designed to prolong the life of the tubeless sealant of the same name, but it’ll also work on its own to get you out of trouble. If you’re using the Silca sealant then this Replenisher makes the initial cost more appealing as the months pass by. As a sealant on its own, though, there are better on the market for less money.

Having reviewed Silca’s Ultimate Tubeless Sealant back in the summer, I’ve had it sloshing around in my tyres for around six months now, a period that happened to include some of the hottest temperatures seen in the UK.

Many sealants can start to dry out in those conditions, requiring a replacement. This Replenisher reduces the need for that, when using Silca’s sealant.

> 9 things they don’t tell you about tubeless tyres

The key to Ultimate Tubeless Sealant, according to Silca, is that it can work at the high pressures found in road tyres thanks to a foaming latex that carries a blend of 6mm, 9mm and 12mm carbon fibre strands to block the holes.

In testing I found it be very impressive, sealing holes in tyres while the pressure was still high, above 80psi, meaning pumping up at the side of the road wasn’t required.

> The 8 essentials to take with you when you use tubeless tyres

Over time the latex part of the sealant does dry out, but obviously the carbon strands don’t, so this Replenisher is basically topping up that latex.

How to use

For the first addition Silca recommends a top-up of 1oz/30ml (in a road tyre up to 30mm wide) after three months; then 1.5oz/45ml after six months, and another 2oz/60ml after nine months, to extend the life of the sealant to 12 months.

If you’re switched on you will note that a 4oz bottle isn’t going to achieve that, coming up half an ounce shy. The Replenisher is available in a 32oz bottle, too, though.

Because of the liquid nature of the sealant, Silca says the Replenisher can be injected into the tyre through the valve once the core is removed. It’s easy to do this if you have a syringe and a bit of tube lying around. Or you can do as I did and pop a bit of the tyre off the rim, add the right amount of sealant, and reseat the tyre.

I’ve tested the sealant again since adding a top-up and it still works in the same way as the original sealant did, sealing homemade cuts into the tyre at similar high pressures.

Value

This 4oz/118ml bottle costs £14, which on its own is pricey. CST’s tubeless sealant is £10.30 for 250ml, for instance, and will perform better than the Replenisher if used on its own.

It’s difficult to gauge value against the majority of opposition, though, as the Silca has a very specific job of lengthening the life of its Ultimate Sealant, and by doing that it makes that pricey sealant less expensive.

Conclusion

If you have Silca sealant in your tyres and you want to continue to use it by extending its life then the Replenisher works well and is worth the investment to lower the price overall.

Verdict

Extends the life of Silca’s impressive sealant, and makes it more cost effective