How does one prevent the valve from clogging?
Caffélatex has become the sealant of choice for tubulars, thanks to its compatibility with latex inner tubes. It is also used with success for puncture preventative treatment of butyl tubes, for road and mtb applications. Thanks to its formula, Caffélatex is benign to valve mechanisms, allowing its use also on tubes/tubulars with fixed-core valves. In that case, the only extra step to take to prevent clogging fix valve mechanisms, is to immediately inflate the tube after injection, so that the air pumped inside will push any residual sealant inside, away from the valve. There might be some clogging events in presence of valve extensions, though. Valve extensions fitted on replaceable valve core valves (threading the valve mechanism on top of the extension) reduce the internal valve opening from 4 to 2 mm, a size compatible with that of punctures usually sealed by Caffélatex. The sealant has obviously no way to distinguish the valve opening from an actual puncture, and tends to “fix” it