So why can some riders go months without any sealant issues or valve clogging, while others seem to be dealing with it weekly?
Short answer yes, any valve can be affected by sealant. Some sealants are especially aggressive, and we have even seen conventional high flow valves clog under the right conditions.
One important difference to understand up front is how the pump connection itself affects sealant movement. The Clik system connects and disconnects almost instantly, so there is very little sustained airflow during removal. That means there is not enough time or flow to entrain liquid sealant and pull it into the valve mechanism. With traditional Presta valves, disconnection often involves a longer pressure bleed, and that escaping air can carry aerosolized or liquid sealant along with it, increasing the chance of contamination over time.
In light of this, the Clik Valve is less prone to clogging when used with good technique.
It also helps to understand the general environment inside a tubeless tire. During riding, or after spinning the wheel by hand, centrifugal forces spread sealant evenly around the inside of the tire. When the wheel stops, gravity pulls that sealant back down toward the rim bed. This happens for every rider.
Where experiences begin to differ is how the valve is positioned during filling, deflation, and slow rotation of the wheel.
If the valve is positioned above horizontal, especially near 12 o’clock, sealant draining from the upper casing can either drip onto the rim bed and rim tape and spread there, or drip straight into the stem itself, depending on where it detaches. In both cases, gravity is working in favor of contamination.
At exactly 3 or 9 o’clock, sealant draining can remain continuous along the rim bed and migrate toward the valve over time, where it can enter the side ports common on tubeless stems.
Positioning the valve slightly below horizontal, around 7 to 8 o’clock or 4 to 5 o’clock, is safer. At these angles, gravity tends to pull the sealant off the rim tape or wall before it reaches the valve opening, causing it to drop away rather than feed into the stem.
Six o’clock is only problematic in a specific scenario. Adding sealant with the valve at 6 o’clock creates a large pool directly below the stem. If the wheel is then rotated upward toward 12 o’clock before riding redistributes the sealant, that pooled sealant can pour straight into the valve. Avoiding that rotation, or positioning the valve slightly off bottom, prevents this from happening.
The same logic applies when deflating. Deflating with the valve slightly below horizontal minimizes the chance that gravity will carry and sweep liquid sealant into the valve.
One additional suggested hack is adding a small drop of light mineral oil to the Clik core, then connecting the pump and pushing a bit of air through. The oil tends to resist sealant fibers or particles bonding to internal surfaces. It is not a bulletproof solution, but it does appear to make a meaningful difference.
Used this way, the Clik Valve tends to stay cleaner and more reliable than traditional Presta cores over long term tubeless use.