Help finding slow leak in tubeless tyre
#1
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Help finding slow leak in tubeless tyre
The rear tyre on my road bike is a tubeless 25mm Veloflex EVO TLR. The tyre was a ***** to mount and when I did get the tyre on the rim, I used my pump, which has an 'air blast' cylinder, to seat the tyre. The air blast was done without the core in the valve.
I don't think the tyre ever properly seated. The tyre would inflate from the air blast, and then slowly deflate. I put some Orange Seal in the tyre, air blasted the tyre again, and again the tyre would slowly deflate. I then put the core in, pumped up the tyre and the tyre held air. I swished the sealant around, waited 24hrs, (the tyre was still inflated) and then deflated the tyre, took out the core, and added more sealant. That was September 1st and 1,500km ago.
Since then the tyre keeps deflating and I have added more sealant two or three times because when I checked the tyre, the tyre was dry. No sealant was present. Most recently I went for a 160k/100mi ride on Sunday. The tyre was firm for the whole ride. Tonight I checked on my rear tyre and the tyre was flat. Again.
Any ideas what's going on with the tyre? Any suggestions on how to stop the tyre from constantly going flat?
Thank you.
I don't think the tyre ever properly seated. The tyre would inflate from the air blast, and then slowly deflate. I put some Orange Seal in the tyre, air blasted the tyre again, and again the tyre would slowly deflate. I then put the core in, pumped up the tyre and the tyre held air. I swished the sealant around, waited 24hrs, (the tyre was still inflated) and then deflated the tyre, took out the core, and added more sealant. That was September 1st and 1,500km ago.
Since then the tyre keeps deflating and I have added more sealant two or three times because when I checked the tyre, the tyre was dry. No sealant was present. Most recently I went for a 160k/100mi ride on Sunday. The tyre was firm for the whole ride. Tonight I checked on my rear tyre and the tyre was flat. Again.
Any ideas what's going on with the tyre? Any suggestions on how to stop the tyre from constantly going flat?
Thank you.
#2
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The rear tyre on my road bike is a tubeless 25mm Veloflex EVO TLR. The tyre was a ***** to mount and when I did get the tyre on the rim, I used my pump, which has an 'air blast' cylinder, to seat the tyre. The air blast was done without the core in the valve.
I don't think the tyre ever properly seated. The tyre would inflate from the air blast, and then slowly deflate. I put some Orange Seal in the tyre, air blasted the tyre again, and again the tyre would slowly deflate. I then put the core in, pumped up the tyre and the tyre held air. I swished the sealant around, waited 24hrs, (the tyre was still inflated) and then deflated the tyre, took out the core, and added more sealant. That was September 1st and 1,500km ago.
Since then the tyre keeps deflating and I have added more sealant two or three times because when I checked the tyre, the tyre was dry. No sealant was present. Most recently I went for a 160k/100mi ride on Sunday. The tyre was firm for the whole ride. Tonight I checked on my rear tyre and the tyre was flat. Again.
Any ideas what's going on with the tyre? Any suggestions on how to stop the tyre from constantly going flat?
Thank you.
I don't think the tyre ever properly seated. The tyre would inflate from the air blast, and then slowly deflate. I put some Orange Seal in the tyre, air blasted the tyre again, and again the tyre would slowly deflate. I then put the core in, pumped up the tyre and the tyre held air. I swished the sealant around, waited 24hrs, (the tyre was still inflated) and then deflated the tyre, took out the core, and added more sealant. That was September 1st and 1,500km ago.
Since then the tyre keeps deflating and I have added more sealant two or three times because when I checked the tyre, the tyre was dry. No sealant was present. Most recently I went for a 160k/100mi ride on Sunday. The tyre was firm for the whole ride. Tonight I checked on my rear tyre and the tyre was flat. Again.
Any ideas what's going on with the tyre? Any suggestions on how to stop the tyre from constantly going flat?
Thank you.
#3
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@jadocs Thank you for the feedback. The wrap on the rim is coming up to three years old now. Question. Do I remove the old wrap first? Thanks again.
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@jadocs Thank you for the feedback. The wrap on the rim is coming up to three years old now. Question. Do I remove the old wrap first? Thanks again.
You may find the old tape has become brittle and just lifts off. Wipe it down anyway.
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First I would dunk sections of the inflated tire in a tub of water to find where the leak is coming from which can make determining what is causing the loss of air much easier.
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No need, the leak is not the result of a puncture, it just slowly deflates which means his tire is not sealing properly. Primary culprits is losing air around the spokes (which means poor tape job or tape is old and no longer doing the job) or around the valve (if the valve is not seating right it can be either operator error, or the tape is in such condition that it prevents it from seating properly).
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#7
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The real key with seating tubeless is to leave the tire/rim sitting flat over a trash can or waste basket so that the sealant runs toward the beads rather than pooling in the tire. Leave it there for 15-30 min, then wave it around a bunch, and put in on the other side.
Dish soap and water is the best way to detect leaks.
Dish soap and water is the best way to detect leaks.
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Thank you everyone for the feedback. Very much appreciated. Looks like I have my winter project!
#10
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Definitely remove the old tape and clean the rim with IPA or Acetone before installing some quality rim tape. I've tried a few of the off brands but always go back to DT Swiss as it has held up far better than the others I've tried.
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No need, the leak is not the result of a puncture, it just slowly deflates which means his tire is not sealing properly. Primary culprits is losing air around the spokes (which means poor tape job or tape is old and no longer doing the job) or around the valve (if the valve is not seating right it can be either operator error, or the tape is in such condition that it prevents it from seating properly).
trev
#12
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Another vote for retaping. Also, regarding @jadocs mention of losing air around the valve, I have found some rims require pressing the valve in very hard from inside the rim while tightening the valve nut to get it to seal. Valves in my HED rims seal up without much effort with the nut just finger tight, but I have a set of Hunt rims where I had to put a lot of force into pushing the valve into the rim to get it to seal. So after taping, when reinstalling valve, pay extra attention to seating the valve. Lastly tape — again @jadocs mention of width is spot on. The tape should be a couple of mm wider than the internal width of the rim. This allows it to cover the concave rim channel while sill covering the rim from bead to bead.
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