Since the video I shot today (lacing a wheel) came out not quite ready for prime time, we'll do a quick ask me anything. Today's question:
"I'd really love to hear about your experiences and thoughts about different tubeless sealants for road bike tires. I've only tried a couple, and what I've noticed is the one that didn't dry out quickly also didn't seal very well. And the one that sealed really well dried out fast and get sticky and hard to remove. I'm wondering where the happy medium is. Especially since it can be really hard to remove road bike tubeless tires to get the goo off before adding more sealant."
As we've said before, we're not the world's foremost advocates of road tubeless. It's okay, and it's gotten better than it was, but it's still not a layup decision. I have actually just made the decision to re-try it, after an atypically tortured decision paralysis about my next tires (going with Schwalbe One 28s - the tan wall sealed the deal). But typically my take has been if the tire has knobs, I go tubeless. If the tire uses more than about 55 psi or somewhere in there, I go tubes. Why?
When I replace a mountain bike tire, I typically find a whole whole bunch of "stanimals" in there, the little coagulated booger asteroids that let you know that you had a flat that you never knew about. Same more or less with cross/gravel tires, but less so. With road tires, I've known when I've gotten almost all of the flats I've had. Because road tires are so low volume, any air loss gets noticed. Because what air volume in there is relatively high pressure, when you get a puncture that air wants to get OUT. Even effective sealants have a hard time up against that. But, in the immortal words of W, fool me once and shame on you, fool me twice and... you can't get fooled again. So I'm going to try again.
We've used all of the shown sealants (and a few more) and they all work to some degree and they all fail to some degree. We have not ever gone to "November length" testing on this. I'm going to start with Orange Seal on the new tires. The knock against Orange Seal is that it goes stale quickly (6 months +/-) in tires. Well I can live with that, if the payback is effectiveness. I use the Continental goop in mountain/gravel tires lately, and quite like it. Stan's is the old standby.
The one I can tell you that has universally disappointed everyone I've heard from is Finish Line. Haven't used it personally, and not likely to based on reputation.
One thing I will recommend is reading the Slowtwitch articles on tubeless sealants. They do a nice job looking at them. Here is their latest update, but within that they link to earlier stabs at it, and they are worth a read.
Any time you say the word "tubeless" is like kicking a hornet's nest, so I will hit "post" with some trepidation here...