One of the most common issues we hear when customers are setting up their tubeless tires with sealant is that the sealant weeps out of the sidewall. This typically looks like bubbles coming out of seemingly nothing on the sides of your tires. This is most common on some high-end tires that are really fast because they have limited material in the side wall. The lack of material or porous materials like cotton that are used create a really fast tire. The small gaps allow air to escape and that takes sealant with it.
Sidewall weeping stops when the latex plugs up the pours so no more air can come out. If you are getting this to any serious level, it may not be a short fix. If you can keep enough air in the tire to ride, go for a short ride around the block to see if you can get it to stop. If you are still getting weeping, it is best to go ahead an add some additional sealant to the tire because all that weeping is going to use up some of your sealant.
The next step is to sit the wheel on its side and allow it to sit, likely overnight. Add the pressure that you would to ride the tire. Give the wheel a spin and shake it back and forth working your way around the tire. This is to try to coat the entire inside of the tire in latex. Once you have done this and are still seeing weeping, rest the wheel flat on one side and leave it overnight. A small trash can is perfect, or you can rest it on two boxes to keep it from tilting to one side. Since you added extra sealant before this step there will be enough to coat the one side of the tire. When you come back in the morning the tire may be flat. If that is the case add air back to a riding pressure. Check the sealant level by shaking the wheel and listening for the pool moving around. If you can’t hear it, there is likely not much left, and you will need to add a bit more. From there shake the wheel to try to coat the inside again and leave the wheel on its other side. When you come back the next day, it maybe a little low but this should solve your side wall weeping issues.
If you have tires that are extremely prone to weeping this badly, you are going to want to be adding Ultimate Tubeless Sealant Replenisher or more Ultimate Tubeless Sealant w/Fiberfoam fairly quickly as it uses the sealant to seal that tire. If you are still having flat tires in the morning after all of this, spray some soapy water on the fully inflated tire to find the spots where it is still weeping. Try to pool sealant in those areas and you will then stop the weeping. Most tires don’t require this level of work to seal, but it can be one of the most frustrating set ups if they do. Have some patience and use sealant liberally and you will ultimately have a great set up to go ride.
Sticky Valve Cores
Tubeless systems with a high-quality sealant are fantastic because they stop air from coming out of small openings. One common issue is the sealant getting into the valve core and doing what sealant does best, stopping air from coming out of that small opening. The problem is obviously that we want air to be able to go through that particular opening. It will often start as being harder to inflate the tire because air can’t move through the valve and then if it is left untreated it can completely seize your valve core where you aren’t able to add or remove air to the tire.
When it gets this bad, unfortunately the answer is likely that you just need to replace the valve core. It is a simple project and if you are running tubeless, you should strongly consider keeping a few spare valve cores around.
They can be cleaned when they start to get gummed up but can be very difficult. SILCA introduced a Sealant Remover product that doesn’t dissolve latex but breaks the bond latex has with surfaces. This is a great use to spray the Sealant remover liberally to a valve core you have removed. Wait 3-5 minutes the sealant will be much easier to remove. You can use needle nose pliers or tweezers to remove the sealant and it will open up the ability to keep using that valve core.
Leaking from the valve or Nipples
Another frustrating issue can be getting air coming through the base of the valve hole or nipples of the wheel. This almost always means that you have an issue with the rim tape, but the first check should be the valve. The valve needs to be finger tight but be careful not to pull the valve too tight. If it is pulled too tight you can make the hole a little too large and it will allow air to leak, and you can compress the rubber compromising the seal.
If you are still getting an air leak at the valve hole or nipples, you want to remove the tire and check the rim tape. Often rims have a release hole for pressure but if they don’t, you want to stop inflating immediately when you see air coming out of the nipple. This is because air is getting in the rim itself and can lead to breaking the wheel since it is not a cavity designed to hold pressure.
Once you have the tire off, clean the rim bed thoroughly. Check to see if there are any punctures at the spoke holes, edges of the tape coming up, or any other obvious source of the leak. You will often then need to remove the tape and replace it entirely. When you replace the tape, you want to be sure that you clean the rim bed extremely well. Choosing a tape that is the right size is also very important. You want to make sure you get a tape that fully covers all spoke holes but not so wide that it makes tires harder to mount. For a full how to on tape a wheel you can check out our video here.
The Tubeless Bead is Kinked
Tubeless tires are often folded up when you purchase them for ease of purchase. It makes it much easier to ship and display in a shop, but it can cause the bead to get kinked. If this happens you aren’t going to be able to get it sealed as air will sneak out under that portion of the bead. The good news is the solution is simple. You can sometimes manipulate the bead by hand to get it back to straight.
If that isn’t possible the easiest way to unkink the bead is to install the tire with a tube, inflate the tire, and leave it overnight. This will allow the bead to work its way straight and ultimately help it seal when you go to set it up the next day.