Are there presta valve diffs between tubes and tubeless?

[smontanaro]

The tubular repair thread reminded me that I have a presta+sealant question. I have Veloflex Vlaanderen on my Griffon and when I first got a flat I shot in some sealant (Orange Seal Endurance). For the most part it's worked well, but every now and then the tire will go flat. There's no sealant leakage to suggest it's actually sealing a hole.

After this happened a few times I started to investigate more closely and found the valve core was gummed up with sealant crumbs. That kept the valve core from closing completely. I carefully cleaned it up with a small wire and all was well. Until the next time.

My question: Is there something about the construction of presta valves used in tubeless setups which prevents this clogging, or is this something tubeless fans suffer with as well?

[Dude]

Most tubeless valves have a removable valve cores so you can get the sealant in easily. Some tubulars have removable valve cores as well. Even some tubes have removable valve cores.

[smontanaro]

Originally Posted by Dude

Most tubeless valves have a removable valve cores so you can get the sealant in easily. Some tubulars have removable valve cores as well. Even some tubes have removable valve cores.

Yeah, that's not my problem. My Veloflex tubulars have removable valve cores. That's how I inject the sealant in the first place. The problem is that the little sealant crumbs get in the valve core from the inside and keep the itty bitty conical rubber seal from fully seating on the valve core barrel. Sometimes I can really twist on the valve core lock nut to get it to seal completely. Sometimes it seems there is nothing I can do but pull the valve core and clean it out with a thin wire.

Given that tubeless valve stems are installed differently (from the inside of the rim, right? I've never used them), I wondered if maybe they have something to keep the sealant crumbs from clogging up the valve core. Maybe a fine screen?

[Mikej]

Op, same thing happens on my mtb’s - I just air them down, remove the core, then run a pipe cleaner wire brush through. Clears it up.

[ColonelJLloyd]

Originally Posted by smontanaro

Maybe a fine screen?

A screen would likely produce the opposite of what is desired, helping aid the clogging.

To answer your question, some tubeless valves have a larger ID at that the base which helps to ward off clogging.