masi61

…it doesn’t! I wasted several hours yesterday trying to re-mount my Hutchinson Secteur 28 tubeless tire onto my DT Swiss rim that I had re-taped with 2 layers of DT Swiss tape.

I re-used the old valve which is the correct one for this rim. The rubber part is rectangular with a slightly contoured top to make the correct seal with the inner trough of the rim. It is supposed to seal when finger tight but that wasn’t working so I tried pliers on the nut (which I already know to be a no-no) & it did not help either.

Arghh!!! My tubeless proficiency I thought was “intermediate level” but once again I am not holding air and thus not able to enjoy these lovely tires. Please make suggestions to help get me back on track!

Racing Dan

Outside of looking it all over to spot any defects, I'm not sure anyone can give you much advice. Maybe the rubber bung is deformed?

What gets me when someone post about this issue (you are not the first) is, why doesn't the sealant plug it up. Cant be much of a gap even if the rubber bung isn't perfect.

Sorry for not offering any useful tips .. :-)

masi61

Thanks for participating in a discussion of a dilemma.

This valve stem is losing air too fast. I was able to pump the tire up to about 110 psi & took a test spin around the block but had to dismount & walk it the rest of the way by my neighbor’s house since it was now flat.

On my next day off I will remove the tire completely so I can get a better look at the rim tape & valve hole. I look forward to riding these wheels but my loss of free time fussing is making me miss out on more interesting things I could be doing with my time on my day off.

Troul 

with the presta valve out, rotate the wheel with the leaking area facing down at the lowest point, allow some of the sealant to seep out just enough to expose itself. With the wheel in its current position, reinstall the presta valve, fill the tire up to the riding psi needed. Let it rest in the current position for a handful of hours. Recheck the PSI. If it has not dropped a significant amount, or any, it should be good to go. If not, then you'll need to disassemble it all, clean it very well, & redo the process per the sealant instructions.

Andrew R Stewart 

First thought is did you apply a skim of sealant to the rim/valve base area? Next is 110PSI in a tubeless tire??? Third is that we find a 3 or 4 layer taping is sometimes needed and the last layer sits centered so to offer the valve base a surface with no tape edge to also seal at.

BTW we are discouraging tires that need really high pressures to do their job with a tubeless set up. For road bikes that often means not running skinny tires which might bottom out over road crap unless pumprd to those high pressures. Andy

masi61

The 110 psi was just what I could get in there to try to test ride around the block & get the beads to settle in. I would have pre-inflated slightly higher still (if I could have) for the same reason.

once I get the tire to hold air I suspect I will run these no higher than 85 (rear), maybe down as low as 74/75 psi.