Pit Stop TNT is a thin sealant and it retained this viscosity when chilled, however we noticed a skin had formed over the sealant when it was heated. For many sealants, this means that the life expectancy is shorter than you might realise. It’s the one aspect of a tubeless setup that can catch many riders out. How long will a sealant last? Unfortunately due to the slightly unstable nature of all sealants, it is not a fit-and-forget solution. Over time sealant will dry out and, in the case of latex-based sealants, will coagulate into a solid lump reducing effectiveness to almost zero.

Then pump to your riding pressure. A tubeless setup should normally be 10-15% lower than the tyre pressure you use if running inner tubes. In the first test, we used two Michelin Wild Grip’R 2 tyres, and tested three sealants with each tyre.They also help form an airtight seal between the wheel rim and tyre when you first mount a new tyre, so that the tyre will hold air and keep its pressure. To find which sealant is best for tubeless tires– and if it actually makes ditching the inner tubes worthwhile – we’ve taken six popular brands and put them to the test. At 7mm, the hole would seal at around 30psi, but it wouldn't hold pressures any higher than that – repeatedly inflating the tyre and the seal would break every time. In the event of a puncture, locate the source and rotate the wheel until it is at the lowest point to enable the sealant to begin the process of plugging the hole. Then rotate the wheel until the puncture is at the top. This will allow the air to get to the sealant and enable the sealant to begin coagulating and plugging the hole. If it still leaks air, repeat the process until it works. Cycling Weekly sat down with founder and president of tubeless sealant maker Orange Seal, John Vargus, to find out his top tips for maximising the efficiency of your sealant.

When we first squirted the full 140ml there didn’t seem like much left in the bottom of the tyre, but we needn’t have worried because this luminous pink gunk sealed the 2.75mm puncture in barely a revolution. It also sealed the larger 5mm almost instantly and, while most sealants on test only sealed the sidewall cut temporarily, NPH sealed it permanently and we even managed to re-inflate the tyre after about an hour. Another sealant stalwart, Orange Seal is a brand with a long history. However, in this test, the results weren't superlative. There definitely is something about long stranded particles that really boosts sealing performance. Although Silca has made a lot of fuss about its carbon fibres and its research, it appears that the Muc-Off sealant works in much the same way, with very similar-looking fibres visible in the plugged holes. Inflate the tyre to below your normal tyre pressure, around 70-80psi, and ride the bike for a few minutes. This allows the pores in the rubber construction of the tyre to open effectively and enables the sealant to really coat the inside effectively. There's more advice on tubeless tyre set-up from an expert in our piece on tubeless tyres: are you doing it properly? What to take with you if you're riding tubelessThe Muc-Off No Puncture Sealant is an ammonia-free solution that claims to seal punctures up to 6mm wide. The formula works for pressures ranging from 15 to 80psi, is CO2 compatible, and should last a long time within a huge temperature range. Stan's No Tubes Race sealant is available in just one size, 946ml, (Quart in US Imperial) and there are some bold claims, including that it will seal punctures “faster and better”, and has twice the particles compared to the standard No Tubes sealant. The sealant uses XL crystals as well as the standard-size particles in the Race version to give better sealant protection - and it should be suitable for use in a wide temperature range, although no exact figures are provided. The reason for this effectiveness as a sealant is that coagulation of the latex is activated by air. So when a tyre is punctured, the dramatic release of air causes the liquid part of the sealant to evaporate, leaving behind the latex rubber particles to knit together and clog the hole. What are non-latex tyre sealants?