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Tubeless won't inflate due to valve

joeyhalloranjoeyhalloran Posts: 1,056
in Workshop
I'm very close to giving up with road tubeless but I'm hoping so one can give it one more chance. I have the muc off valves, schwalbe pro one tyres and Hunt gravel/4 season wheels.

I am having an issue where when I inflate the tyre with an air blaster the tyre seats initially but goes flat in 5-10 seconds and it feels like the air is leaking out around the valve. Hunt have asymmetric rims so the o ring between the nut and the rim is being deformed in a strange way, I thought this might be the issue so I tried with the nut the other way round and no o ring but I got the same issue, air rushing out around the valve and none staying in the tyre. These tyres and rims have been inflated together before but with a different valve. I wanted to change the valve for one I could inject sealant through rather than having to pop the tyre each time.

Can anyone help?

Posts

  • whyamiherewhyamihere Posts: 7,677
    Does it stay inflated with the original valve? I've never had a tubeless valve which can't have sealant pushed through by the way, all the ones I've ever had have had removable valve cores, that's all that's needed.
  • joeyhalloranjoeyhalloran Posts: 1,056
    Yes, it has sealed with 2 previous valves. Perhaps I was overconfident but I think I threw the old one away when I put the new one in (thinking I could get it to seal somehow, I'm not regretting that)
  • whyamiherewhyamihere Posts: 7,677
    I was meaning does it still seal with the old valve, though that might be hard to test if you have thrown out the old one. The reason is that a failure in the rim tape could escape via the valve hole which would make it seem like the valve is at fault.
  • joeyhalloranjoeyhalloran Posts: 1,056
    It doesn't look like the rim tape is damaged but I appreciate that sometimes these things are hard to see. Though I would expect if it's damaged rim tape it would take longer than ~5 seconds to empty the tyre?
  • ed1973ed1973 Posts: 284
    Muc off valves come with 2 types of seal that goes between the valve and the rim, have you tried the other rubber seal to see if that works. I had the same issue with my hunt wheels and when I switched the seal it sorted the problem. Another issue could be the seal is correct but has twisted in the recess of the rim when you tightened it up.
  • lochindaallochindaal Posts: 475
    assuming you have the sealant in the tyre already you could try to loosen the nut and let a little sealant come out then hand tighten again. The sealant may stop the leak. Don't over tighten the nut to "fix" the problem.
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  • joeyhalloranjoeyhalloran Posts: 1,056
    ed1973 said:

    Muc off valves come with 2 types of seal that goes between the valve and the rim, have you tried the other rubber seal to see if that works. I had the same issue with my hunt wheels and when I switched the seal it sorted the problem. Another issue could be the seal is correct but has twisted in the recess of the rim when you tightened it up.

    Interesting, which seal did you use? There is the original curved pyramid type one, straight sided cone and a rectangle one. I tried the original one and the rectangle but haven't tried the straight sided cone type one yet
  • ed1973ed1973 Posts: 284
    Try it, nothing to loose, just really don’t over tighten it, solid finger right normally does the trick. Ps I’m going to assume the tyres are tubeless ready, just checking.
  • joeyhalloranjoeyhalloran Posts: 1,056
    Yup, and they've been run tubeless in the past without issue.
  • joe_totale-2joe_totale-2 Posts: 1,333
    Is there sealant in there? If you pop some in, make sure it coats the tyre well and leave the valve at the bottom then it may seal up the holes which are causing the air to leak.
  • joeyhalloranjoeyhalloran Posts: 1,056
    Ok, I persuaded my 7 month old to sleep well enough for me to have another go this evening.

    I took the tyre off, cleaned up all the dried sealant stuck to the bead of the tyre and remounted the tyre (coated in sealant). I also switched the seal on the inside of the valve and coater the rim with soapy water. Still nothing, but I'm now starting to think the tyre isn't seating properly and what I thought was the valve leaking is actually just my tubeless blaster. One thing I did notice was how easily the tyre now goes on the rim. Im sure when I first got them and set them up last year they were tighter. Do tubeless tyres stretch over time? And if I add a layer of rim tape for this tyre will I have issues when I come to fit a new, unstretched tyre?
  • mully79mully79 Posts: 904
    ive never succesfully re-mounted a previously well used tyre no matter how much effort has gone into cleaning the bead. Treat yourself to a new tyre.
  • mattsccmmattsccm Posts: 408
    If in doubt another layer of tape solves virually all tubeless issues.
  • NcovidiusNcovidius Posts: 229
    Tubeless can take a while to settle properly. I swear by road tubeless now, the last set of tyres I used did take a while to seal up properly, I had to rotate the wheels a lot, and look for sealant leaks. Eventually I did get the seal I needed, they don’t lose air much more than tubes, and are a lot less hassle in every day use. It’s worth persevering.
  • imposter2.0imposter2.0 Posts: 12,015
    Ncovidius said:

    Tubeless can take a while to settle properly. I swear by road tubeless now, the last set of tyres I used did take a while to seal up properly, I had to rotate the wheels a lot, and look for sealant leaks. Eventually I did get the seal I needed, they don’t lose air much more than tubes, and are a lot less hassle in every day use. It’s worth persevering.

    It would be priceless to dig up all your old 'anti-tubeless' posts at this point, Nick...

  • Charlie_CrokerCharlie_Croker Posts: 1,660
    joeyhalloran said:

    Ok, I persuaded my 7 month old to sleep well enough for me to have another go this evening.

    I took the tyre off, cleaned up all the dried sealant stuck to the bead of the tyre and remounted the tyre (coated in sealant). I also switched the seal on the inside of the valve and coater the rim with soapy water. Still nothing, but I'm now starting to think the tyre isn't seating properly and what I thought was the valve leaking is actually just my tubeless blaster. One thing I did notice was how easily the tyre now goes on the rim. Im sure when I first got them and set them up last year they were tighter. Do tubeless tyres stretch over time? And if I add a layer of rim tape for this tyre will I have issues when I come to fit a new, unstretched tyre?


    You mean you’re not *sure* where the air is escaping from!
    First things first, get a bowl of water

    Make sure your attacking the actual problem…

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