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Discussion Starter #1
Last race season I race my tubeless setup with no issues at all and this spring I started to consistently loose pressure in my rear. I aired up a few times and after a day of sitting around the tire would be flat. I had stans in the tire as well. After frustration... I bought a new tire (same as I had) Maxxis Ikon had a LBS re tape the rims (2x around) with a new stem. Pumped it up to 45 to let things set for a while, swished the stans around as well. About 6 hours later I aired down to 25 for my ride and all was well. The next morning the tire was flat again. Aired back up, later that day flat again.:madmax:

Any suggestions/Ideas? Im getting pretty annoyed with it. Help would be much appreciated.

Thanks!

Running Stans ZTR Crest Rims w/ Maxxis Icon 3C/EXO/TR
 

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mtbpete
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There can be many sources of leaks. New tires, that are not tubeless sometime develop micro-holes in the sidewalls while sitting under pressure. Sometimes the tape in the rim gets bunched up and air gets around it. The easiest thing to do is to pump up the tire and spread a thin sheen of soapy water all around the tire and look for places that suds occur. Shake the sealant to the areas where suds occur and repeat. If you see air bubbles at the valve area or the spoke nipples then sealant is getting around the tape and you need to take the tire off to fix this. Good luck!
 

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SS Pusher Man
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Perhaps they didn't do a very good job of removing the old Stan's from the bead of the rim before the put the new tire on.

Or, since they retaped the rim, perhaps the valve stem is not on tight enough.
 

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Rocks belong
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Fill bathtub with 6-8" of water and put the wheel/tire in it... rotate the wheel and look for bubbles.
 

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if you're not seeing any sealant on the outside of the tire, could it be leaking at the valve? It happened to me and it can be confusing because air will leak out the small vent holes in the rim. In case the valve base doesn't seal properly with the channel in the rim, I put the o-ring on the inside of the valve stem and it seals better.
 

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If you or they didn't do it, highly suggest you only use 1 wrap of STANS tape and then install a tyre with tube to help press the tape onto the rim. Of course you nee to properly clean any residue left back from the old tape and any sealant stuck in the bead hook, also I find putting a bit of sealant around the rubber of the valve helps make sure it seals good.
 

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I had a problem with my Stans valve stems leaking. I was installing them after the tape, through an X cut in it. This didn't work. I had to put the valve, with a smear of stans in it, directly in the rim, tape, cut a hole for the valve, put another strip of tape over the valve and cut a small hole for air. It worked for me.

I will warn, it was a mess after it leaked past the valve because sealant was inside the wheel. It kept coming out of the spoke holes. An air hose and 150 psi got it out enough to clean it for the tape to stick
 

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You don't cut a freakin "X" in the tape, the cuts will just keep on going, you "punch" a hole with the valve carefully or small punch or philips screw driver that's heated.

I had a problem with my Stans valve stems leaking. I was installing them after the tape, through an X cut in it. This didn't work. I had to put the valve, with a smear of stans in it, directly in the rim, tape, cut a hole for the valve, put another strip of tape over the valve and cut a small hole for air. It worked for me.

I will warn, it was a mess after it leaked past the valve because sealant was inside the wheel. It kept coming out of the spoke holes. An air hose and 150 psi got it out enough to clean it for the tape to stick
 

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You don't cut a freakin "X" in the tape, the cuts will just keep on going, you "punch" a hole with the valve carefully or small punch or philips screw driver that's heated.

Stan says to cut an x at the valve hole. I followed their instructions and it worked just fine, cuts did not "just keep going".
 

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SS Pusher Man
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You don't cut a freakin "X" in the tape, the cuts will just keep on going, you "punch" a hole with the valve carefully or small punch or philips screw driver that's heated.



 
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I've done this a few times and find my best luck by using one wrap of stan's tape (after deburring the nipple cutouts), burning the valve hole in with a hot wire (chunk of hanger wire heated with a lighter or soldering iron tip), inflating with a tire and tube for 24 hours, then setting up for tubeless. If you have any gaps in the tape and your sealant gets in there you're hosed. If you're rims have burrs around the nipple holes stan's cuts just like any other thin rim strip.
 

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Any time I've had issues was when I did it that way without using the file after, but if you do use the file after, then it's not normally an issue as it stops the cuts from tearing more. Think I did it the "proper" Stans way the first time I taped my first set of rims, after that I used the hot poker method/valve stem with great success.
I freakin do that all of the time with no issues!
 

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Hey man, sorry my post got pushed down a bit. My response was to the user who said that you should never "freakin" cut an x in your tape to install the valve stem.

I agree, any burrs present on the rim should be filed down. That stuff is sensitive to sharp edges.
 

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Discussion Starter #15
Great tips. So basic steps of suggestion:I guess I'm just going to remove tire, clean everything really well, paying extra special attention to the bead lock. remove the old (brand new) tape and stem. Re-tape only 1x around.

  • remove tire
  • remove old (actually brand new) tape and stem
  • clean really well with extra care to the bead lock
  • retape 1x around
  • puncture for stem
  • insert tube and tire and inflate to seat the tape really well
  • remove tube and insert stans stem w/ some extra stans around it
  • mount tire and insert 2-3 oz of stans
  • inflate to abour 45 psi and work it all around for about 10 min
  • all set
  • air down to appropriate pressure after a couple hours

sound about right?
 

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Fill bathtub with 6-8" of water and put the wheel/tire in it... rotate the wheel and look for bubbles.
^^^ This should be step one before doing any more dismantling, filing, tape removing, sealant slathering, etc. Find where it is leaking first before blindly applying all sorts of fixes at once. If you see bubbles coming from tiny pinholes in the tire casing, then my opinion is a short ride at your normal inflation pressure is the best way to distribute the sealant internally to coat everything and plug those little holes. Sometimes stubborn sidewalls might require the shake and spin and lie flat treatment. But honestly, a short ride has always done the trick for me.

Take heed of changingleaf's comment on, "If you see air bubbles at the valve area or the spoke nipples then sealant is getting around the tape and you need to take the tire off to fix this." That's when retaping is the appropriate troubleshooting step. Although bubbles at the valve area could just mean you need to tighten the stem nut harder.
 

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mtbpete
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Hi riders. Note: the dunking-the-tire-in-water method does not work very well for very small holes. - These will be much easier to find with soapy water. Spread a thin sheen of soapy water on the tire and look for areas where suds occur, then shake the sealant to these areas and repeat. - This done correctly will allow you to seal ANY tire.

Also, air leaking out the valve area almost never means that the valve is not tight enough. The valve is not sealed on the outside of the rim so any air in the cavity of the rim will come out the valve area. The air pressure in the tire alone is enough to compress the valve against the inside of the rim to seal it. So if you see air or sealant coming out the valve area then you most likely have air getting under the tape in the rim, which goes into the cavity of the rim and out the valve area.
 

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West Chester, PA
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I've never used a tube to make tape seal. Cleanliness and stretching the tape properly is key. Then I put a towel over the ends of my fingers (so they slide) and press firmly as I spin the wheel around on my lap. But, whatever floats your boat.

As for the valves, press very firmly on the valve gasket with one of your thumbs while your other hand tightens the nut. This will seat the gasket much better. IMO, if the gasket isn't slightly egg shaped, the nut isn't tight enougb. I loctite my valve nuts too but some people dont like that suggestion cause it can make removing a valve on the trail very difficult.
 
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