Hi all, looking for tubeless advice. I have a situation where my Continental GP 5000 TL on my Zipp 404 wheels will leak at a specific bead rim connection point. The sealant will bubble out slowly but not seal. This will lead to the wheel deflating in about 15 minutes. Anyone have any suggestions on what to do to get the sealant to seal that issue?
Is the tyre seated correctly? Sounds a bit like the bead hasn’t fully moved into its place. If it is, is there any damage to the tyre or rim? Has the rim tape moved? If you rotate the tyre around a bit, so that the spot is at a different point of the rim, does the same still happen?
(Also, I usually make sure the tyre is seated fully, and then add sealant. Much less mess.)
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I ensured the bead was seated using an air compressor. The tire does have some damage, puncture that was sealed using a plug, above where the tire is having trouble sealing. Have tried moving the tire.
I like Stans/Joe’s but avoid FinishLine; I used the latter forca bit and found it couldn’t sealant anything. On a ride I’d get a tiny p’ture which FinishLine couldn’t seal and the tyre would lose enough pressure that hitting something like a cateye would be enough to unseat the tyre. I almost gave up on road tubeless until I realised the FinishLine sealant was the problem. Touchwood Ive been nearly 4 years without a unscheduled deflation and barely have to worry about loss of pressure.
I use Stan’s sealant
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I doubt its a sealant issue then. Ive not got Zipps but I have 5000TLs and they hold their air good for me. At a very random guess going by the last time I replaced a 5000TL and it wouldn’t seat first off. A bit of old sealant had got into rim and stopped the tyre seating fully. After I cleaned the rim it seated fine (popped into place). Other times I have used a CO2 cannister to make that initial seat when I don’t have a compression tank to hand.
Does it ping into place? Is the line on the side of the tyre the same distance all the way round?
How did you fix the old damage, is the plug still there, or did you fix it with a patch instead? It could be that it only looks like it is leaking at the rim, but really is leaking from the puncture. There could maybe also be a second puncture close to the bead?
Sounds like it’s new tire day.
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I’d put my money on there being a secondary puncture near the bead - if thats the case then i would say new tyre unfortunately.
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How would I identify a second puncture?
David
Any chance the rim is bent in that spot?
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Pump it up, and look very carefully where the air is coing out from. It might help to put your finger over any suspect places, it might be easier without sealant, because it doesn’t get as messy.
If the puncture is under the rim, or very close to it, any movement will often open it up again - so yeah, in that case a new tyre will make sense.
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Agree with others - I’ve had similar with sealant bubbling out of the rim joint. The rim was fine but there was a snakebite puncture just above the bead of the tire. I’d try a new tire (and if it’s still happening then it’s a strong possibility that the rim is damaged)
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Pump the bad boy up to 1.1x recommendation, you may not have it seated properly. That was certainly my experience when i had a similar issue previously.
I’d remove the tyre and carefully inspect the inside - I suspect you may have fixed half of a snakebite puncture.
Is there any dried sealant from a previous install along the bead in that location? Or any dried sealant along the rim/bead interface in that spot?
If the tire already has a plugged puncture, I’d probably just get a new tire.
Sometimes they are hard to spot. I flatted in a MTB race last year with a snakebite puncture. The hole in the tread sealed fine, and I thought all was good until the tire was flat again a few mins later. Closer inspection showed a small hole by the bead. It wouldn’t seal, so I had to put in a tube. I replaced the tire the next week. You might just need a new tire.