I’ve been running Caffelatex sealant in some latex tubes this year. Some things I’ve learned;
Sealant in a latex tube will lower the rate of pressure loss by about an order of magnitude. For what that’s worth.
Caffélatex states that sealant in tubes lasts longer than it does in tires. From their site:
- tubular (or inserted into a butyl/latex/polyurethane inner tube): up to 1 year
- tubeless tyre: 2-6 months
- tubeless-ready tyre: 1-4 months.
I can only speak to latex tubes but - if you deflate the tube all the way, either by neglecting to add air for a couple of months, or when moving the tube between tires, then the inside of the tube will immediately stick to itself. If you catch it within the first minute or so when it happens, you can re-inflate and the sides of the tube will separate with no apparent damage. I’ve done this a couple of times and the amount of force and stretch on the tube doesn’t seem risky to me
But beyond a minute or so, I can’t speak to whether you can safely separate the sides. I’m guessing you probably could for at least a few minutes longer, but I would toss a tube without hesitation if it sat empty for a day.
Just like with full tubeless, you have to avoid bleeding air when the valve is at the 6 o’clock position, or you can get sealant in the Presta valve and cause a clog or get the valve stuck open. Early on I had one flat due to this, where I hadn’t taken good precautions, and I got a leak that was too slow to detect. Since then I’ve been more careful and it’s never recurred.
I’ve never had a puncture so I can’t speak to how it seals. Based on what I’ve read, I don’t really expect it to work, but I hope to be pleasantly surprised.
Unless I actually experience them sealing a flat, I probably won’t do this again next year.
The one instance I might is for a long course A race, where I want to run latex tubes but it would be nice to not worry about losing air pressure over the day, and it would be worth having that tiny bit of extra defense against a flat.
I do worry that changing a flat would be harder, since sealant would presumably get all over the tire and rim.