We often receive questions about Caffélatex solidification after the inflation of the tyre with a CO2 cartridge. This is a known and unwanted side-effect related to CO2, common to most latex-based sealants.
While Caffélatex resists well to both low and high temperatures (between -20 and 50°C), sudden temperature changes are not good for its stability. A strong thermal shock could be a polymerization-starter for any latex-based sealant (natural or synthetic), so we suggest to limit the use of CO2 cartridges or, if necessary, to do it with extra care.
Follow these tips to avoid negative effects:
- given the fact that the biggest thermal drop is close to the valve, use the CO2 cartridge keeping the valve on a 12 o’clock position. With the valve in that position, wait some seconds before inflating, to permit the sealant to flow down, so to escape most of the temperature gradient;
- use adjustable CO2 adapters (connecting the CO2 cartridge to the valve) to control the inflation rate. By keeping low inflation rate, you will prevent solidification issues. The temperature drop is indeed connected to the CO2 expansion rate: if the expansion is slower, so is the inflation rate and the temperature drop; this way you save your sealant and avoid freezing your fingers.
Don’t hesitate to use Espresso inflate & repair cartridge when your tyre already contains Caffélatex. The typical CO2 cartridge has a pressure much higher than the one of Espresso sealant (which uses Propane), so the expansion of the gas is more brutal with CO2 than with Espresso. If you think about it, a 16g CO2 cartridge can inflate a road tyre 23-622 up to 8 bar pressure in just a few seconds, while Espresso takes almost a minute to inflate the same kind of tyre up to 5 bar.