Tubeless tire beads unseat everytime i deflate my tire

Does anyone else have the problem of their tubeless tires bead popping off everytime you deflate them?

I’m running Schwalbe Pro One’s on Bontrager Aeolus Comp Disc Tubeless Ready wheels with Stans tape and sealant.

I have an airshot cannister that I can use to inflate the tire with the valve core removed (pump it to 160 psi and dump it in the tire) but when I have to deflate it to put the valve core back in the tire beads pop right back out and I can’t inflate them with the valve core in. I’ve left it pumped up with sealant for 24 hours (airshot cannister attached so it doesn’t deflate and shaking the sealant all around) but still unseats when I deflate it. Ended up getting a LBS to put them on (not sure how they did it) but I had a puncture on the weekend and I’ve cleaned out the piece of glass that did it but now I can’t seat the tire back on the rim… Super frustrating

Any tips and tricks from people who have had a similar issue would be greatly appreciated


Hmm, that’s troubling. Do the Pro Ones easily slide on the rim? I’ve got different rims and have run Sector 28s, Pro Ones, Specialized S-Works Turbo Tubeless, and Zipp Tangente. Even the Conti GP4Ks “pop” onto my current rims, but not on the stock Bontrager alloy tubeless ready wheels that came with 2015 Domane 6.2 Disc.

Also, when removing valve core do you hang the wheel off the ground? A few of the Sector 28s I’ve used were out of spec and too loose for my current tubeless optimized wheels. One resulted in a bead failure in the middle of a national forest, on an 18 mile descent. No cell coverage. Anything that goes on too easily makes me suspicious. That said I’ve had no issues with sizing of Pro Ones and fit on wheels.

Tubeless tires will generally do this if you let them deflate all the way. Usually what I do is remove the valve core, air up the tire so the bead seats on the rim, pull the pump off the valve stem and immediately put my finger over the hole. Then, quickly insert the valve core and screw it in. This will let air out but if you do it quick enough, the tire will stay on the bead and you will be able to pump the tire up after the valve core is fully inserted.

The bike shops use high powered air compressors to do this so that they don’t have to take the valve core out. You can get an air compressor for your garage if you have one for pretty cheap. A small one will do the trick usually.


I lay them flat on bucket so that the tires aren’t touching anything and they aren’t deformed in any way.

The Pro Ones go on with a bit of effort but nothing crazy. I think the fit is pretty good

I’ll give this a go Ian. See how fast I can move to keep some air in them, just have to remember to put the sealant in first!

You wouldn’t happen to have any recommendations on cheap high powered air compressors that would suit fitting tubeless tires would you?

FWIW I always remove valve core, and same with two local bike shops. The tires should set on the bead, unless you have sketchy rims, tires, or sealant under the hook on rim. Hope that helps.

I have the exact same combination of tire, rims and rim tape as the OP.

When I first installed the tires they popped onto the rim no problem. However after a month or two I let the air out and the front tire popped off the rim and then proved very difficult to reseat. I have a compressor in my garage and I still needed to remove the valve core to get in enough air to pop the rim back on, then quick put the valve core back in without loosing too much air.

It’s a bit of a faff! I have considered getting the Bontrager specific rimstrips to see if that helps.

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Have you tried the initial inflating / seating leaving the valve core in? I use an air tank to quickly dump a load of air in (like you) but have never needed to remove the valve core for this to work.


I removed the valve core, put the sealant in, attached the airshot cannister, pumped to 140psi and let it in to seat the bead. Then pumped the tire up to 100psi through the airshot cannister, quickly removed the airshot and put the valve core back in as fast as I could and the tire stayed on the rim. Pumped the tire back up to 100psi and I’ll see if it’s held the pressure by tomorrow night. I usually run it at 80psi but leaving it higher just to be sure

Thanks people! Help much appreciated!


great news!

For what its worth, this is the process I use after seeing it at two local bike shops:

  1. Put tires out in the sun for an hour or two to loosen up.

  2. Put tire on wheel, ending at the valve core. Always need to put tire in center of wheel to finish the job. If the tire is very tight, might require loosening valve core stem and pushing the “block” up into tire to give a little more room.

  3. Be certain the tire is straddling valve, otherwise tire will not seat. Sometimes I forget this step and have to repeat.

  4. Remove valve core. Using compressor inflate to seat bead under hook. Let air out. At this point I’ve never had the tire unseat if it popped on.

  5. Add sealant, what works best for me is to hang tire from garage ceiling using a rope.

  6. Reinsert valve core and hand pump to desired pressure.

After 4 different tubeless tire brands I’ve never had to quickly reinsert valve core. My wheels are “tubeless optimized” and most tires require strong thumb pressure to put on the rim. There are tight tolerances between rim and wheel for safety reasons, if a tire easily slips on rim be suspicious.

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Glad you were able to get it all seated! This is the air compressor I personally use: PORTER-CABLE 6-Gallon Portable Electric Pancake Air Compressor


I have the same one, works great.


You obviously don’t live in the UK then!

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On one of the TR podcasts @Jonathan recommended using a hair drier to do the same job, I have used this several times and it works well in the absence of sunshine !


I just had the same problem. Schwalbe pro 1 tubless 700x28 on a DT Swiss R32spkine rear wheel. In anticipation of trouble I got the schwalbe tyre booster and easy fit mounting fluid. The tyre seated beautifully bit popped off the bead when I removed the tyre booster ( its screw on) to try to add sealant and the valve core, because I know its important. I cleaned off all the mounting fluid thinking it was making it too easy for the tyre to slide out but had the same problem. I put in the sealant first but still had the same problem. In desparation ( on the third day!) i just used my track pump directly on the valve with the core in and it took. It seems the schwalbe tubeless easy system means you don’t need all the addituonal tools meant to make it easier?

I’ve been able to set up all my bikes tubeless with no special tools and a floor pump

  • Road/gravel bile with 32, 35 and 37mm tires
  • 2 mountain bikes with 2.4” tires
  • Fat bike with 4.6” tires
    I think with the right

I’m no expert here…but take this with a grain of salt.

I recently got a set of Hunt gravel rims to use for CX racing. I mounted a set off Donnelly pdx. They were VERY loose on the rim. So…I just kept adding rim tape until they were tight on there. Then I was able to mount the tires without taking out the valve core. Was a cinch once I filled in the excess space. Was able to race cross at under 25psi without burping.


This for the win.
It doesn’t matter how hard they are to get on the rim. It’s all about the *skirts of the tyre touching the rim tape when inflating. 0.5mm will make all the difference.
(*Skirts is what I call the thin bit of rubber at the bottom of the bead).
I say this because I lost a whole day of riding in the Blue Mountains because of a loose set of tyres awhile back. I had plenty of sunshine and heat guns. plenty of HV air compressors on hand.
An extra layer of rim tape. Problem solved too late.

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While there are some tyre/rim combinations that just seem not to work, IME most tubeless problems come down to rim tape. Whether it’s a matter of not being fitted correctly or there not being enough, getting the taping right will solve it.

My routine is:

  • Unwrap tyre and allow to get somewhere near its proper shape, ideally in a warm place.
  • Clean the rim
  • Apply rim tape
  • Insert valve and remove valve core
  • Mount the tyre (making sure to observe any directional markings :roll_eyes:)
  • Inflate the tyre making sure it’s mounted securely and evenly all the way around.
  • Remove pump and add sealant
  • Replace valve core and reinflate to desired riding pressure.
  • Go for a ride.
  • Check the sealant and add more if necessary as some tyres soak up the initial shot of sealant so there isn’t any left to deal with punctures.

When inflating/mounting the tyre if the tyre doesn’t slide easily across the rim tape you’ll need some form of air reservoir to give it a kick - I’ve an Airshot - but I’ve mounted fat bike tyres using just a track pump so while it makes things easier it’s not essential.

Tubeless can be either really easy or really frustrating, I’ve had a tyre mount and stay inflated without sealant for 48hrs but the next wheel using the same tyre on the same rim wouldn’t inflate even with an Airshot.

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