DowneasTTer

Ok what’s the deal with tubeless tape and valves? Is there some kinda of secret handshake or incantation that needs to be done when putting new tires on existing tubeless rims? I have been experimenting with running tubeless for the past 2k miles. When I first set them up using Stans tape and valves all was well until I experienced a side wall tear due to glass on my wife’s bike. Not a problem replaced the tyre and by the next morning it was flat. Did a water test and found the valve leaking. Now it was fine before the tyre replacement. At the local Giant shop I purchased new tape and valve (with an o-ring. Worked wonders. So when I replaced my rims (one was found to be defective) I used the Giant stuff instead of the Stans. All was well for about 1k and I needed to replace a front tyre. Did the exchange in the pm and by the am the tyre was flat again. Did a water test and found not only the valve leaking but some spoke nibbles as well. Just finished tearing apart the wheel again…. New tape and new valve and it appears to be holding.

Any ideas as to what is going on? Do you really need to change out rim tape and use new valve for a simple tyre change? Not very likely…. Maybe back to tubes

pdoege

It has been my experience that the first time I try a new wheel/tire combination that I have to dance around to figure out what works best.

The only wheel/tire combo that has worked out of the box for me is Mavic.

However, a general rule that works for me is two wraps of Stan's, an o-ring stem with a dab of contact cement, and injecting a LOT of sealant for the first inflation "slosh it around period".

It sounds like your tape was moved/knicked in the installation or perhaps it was never particularly well bedded?

Anyway, yeah, it can be frustrating until you get it right. Good luck!

DOS

mtbikerinpa

No problems with the mavic UST certified rims and tires as well as UST rims with Bontrager TLR series tires. Some tires vary slightly in bead fit and certain rim strips may or may not seat properly with certain rims. In some instances I have used a bit of RTV silicone on the base of the valve portion of the strip where it seats into the rim to help seal off the valve stem. It is not however out of the question to need to tension the nut after a tire change because of the bending possibility on the seating. Remember with strips it is essentially a rubber band and rubber elasticity will decrease with age. The strip needs to have a fair amount of tension in order to maintain a seal.

dsaul

Did you tear the tape with the tools you used to remove/install the tires? I have done that a few times and had to replace the tape.

LesterOfPuppets

So far I'm at about 33% for how often I need to replace tape with a tire change. 0% for valves.

If the valve doesn't seal on tire change I'd remove it, clean the rubber stopper and reinstall. If it's not sealing, tightening the locknut with needlenose pliers usually does the job for me.

DrIsotope

Some tape is better than others, some valves are better than others. The tape also really needs to be the proper width for the rim, and must be applied evenly, with no bubbles. Or it's (probably) gonna leak. I think I taped a rim two or three times before I got one leak-free.

You definitely shouldn't need to change tape or valve when changing a tire. But if the tape stuck to the tire and got pulled up when the tire came off, that was poorly installed tape from the outset, and it will need to be done again. I don't remove a stem unless the tape is being replaced. There's no need.

DowneasTTer

Thanks for all the suggestions. The tape I'm currently using is Giant made by 3M. Seems to work well. After some thought I think was happened is the valve stem must have moved around enough to allow air to leak into the spoke channel and that was the source of spoke leaks. There wasn't any evidence of tape damage. But, as I so often do, I drove through the swamp and change out the tape anyway. The Stans valves don't have any o-rings and a round rubber seal where the Giant ones have the typical rubber base that fits in the rim channel. I guess I'm just having beginners luck.