I have a small tubeless puncture that sealed up pretty well in a TT (23c corsa speed at 90 psi, finished at around 60 - respect the Stans). Pumped it back up at home and it held 90 ok overnight, but again this evening it went slightly on the test in the same way, down a third.
Just had it off the bike, reinflated in a basin of water and there's not a peep out of it - clearly the forces when riding it are causing it to partially fail and I'd like to patch it. How would you locate the puncture, short of riding it 10 miles round the block until it goes?
Do you think you'd see a build up of latex on the inside where the puncture is? I'm guessing it's a really small hole.
Keep pumping. The latex plug will pop out - eventually...
Keep pumping before every ride for a few months, top it up every week, replace the tape, try a new tyre, then eventually give up and put tubes in.
Then two years later repeat the cycle thinking that maybe you were just unlucky last time and road tubeless might be better now.
Speaking as someone who tried in 2015, 2017, 2019, 2021 and now have just given up after 3 months of commuting tubeless faff 2023 and gone back to tubes.
Have been happily using tubeless on mountain bikes for over a decade.
Keep pumping. The latex plug will pop out – eventually…
I'm feart it'll blow off the rim - wheel is rated 100 psi. I'll give it a cautious inflate to around a ton and see what happens.
My lad had something similar w Hutchinson tyres, the rear had a tiny puncture that would not seal.
I've been running Bontrager R3s (light puncture protection) without problems for a few months, so he fitted those and he's had no probs since.
My BiL is running R3s w tubes, and he's having to change tubes every couple of months.
You could try a bit of Stans Race? It's meant to be magic so it may properly fix it
FYI I've never used it, so this is just a speculative suggestion
As Peekay says tubeless off road, tubes on road
If the air is still getting out somewhere, putting in a bath of water will show you where. Then plug if it's a puncture or more jizz/shoogling if it's leaking at the bead.
I’m feart it’ll blow off the rim – wheel is rated 100 psi. I’ll give it a cautious inflate to around a ton and see what happens
Is that 100 PSI tubeless or with a tube? Tubeless limit is usually quite a bit lower, even 90 seems high for a tubeless setup.
Having said that I never bothered with road tubeless either when I owned such a bike.
Have you tried changing the valve core? Worked for me recently.
If you have already tried the holding it underwater method then not sure you will ever find it.
I would pump it up to 100psi and then hold each section under water for a few minutes as sometimes it is so slow that a bubble only pops out every 30 seconds or so. Hold the whole valve under water too.
Other than that do what others and myself have done and just run a tube. I love tubeless on lower pressure tyres off road when getting punctures is very common with tubes but on road I am not sold on the faff. My tube only tyres running TPU tubes are lighter than tubeless and I don't tend to get punctures on the road but presumably the rolling resistance is very slightly higher.
I would say it's more likely to be the tape or the valve. That's where I would be looking first.
Have you got a UV light? Some sealants glow under UV light to track down leaks.
Although I agree with others and would swap out the valve core first.
If you can locate it, let just enough air out so you can squeeze the tyre to open up the hole a touch.
Then drop a little Loctite 480 in there, let it cure fully before inflating.
Worked for me on a Corsa tub, held 100 psi comfortably after that until it wore out.
Lots of friends have run Corsa tubeless by the way, many have suffered punctured with them.
Sounds like the sort of punctures I've had on the gravel bike where the tyre has been pinched near the bead. Holds air fine until riding forces cause it to flex and open up the hole.
Maybe inflate only so hard such that you can still flex the tyre by hand, then do the bucket of water test, flexing the tyre back and forth under the water?
Once found you can just patch the hole from the inside 👍
Thks everyone - I cleaned the outside of the tyre and let it stand overnight at 95psi and could find the puncture this morning. There was a v small wet spot visible.
@Haze that is a nice fix to know and sounds like it rescued the tub - I'll prob patch this one just to be on the safe side.
@legometeorology this was Stans race actually and I'm v impressed it sealed - pretty much the smallest volume, highest pressure tyre you would see nowadays. There are limits, though - I've had a couple of glass punctures this season riding out to events when it's been raining, and they flatted. Not massive holes, but something 3-4 mm is too much for a tyre this size I think.