I got two brand new Tangente tubulars, and after installing valve extenders on them I noticed they both developed a small leak right at the base of the valve stem, in the tube which is visible after submerging them in water. How it’s possible to get the exact same leak on two brand new tires is beyond me, but what should I go with to seal them? Should I add some Pit Stop, let it sit overnight and then drain the Pit Stop? It doesent seem like a good idea to keep a liquid in the tire for permanent usage as I assume it could dry out.
The leaks are not coming from the extender, they are coming from the base of the tubular, out of the hole in which the valve exits.
Only thing I could think of is the tube got damaged while I was screwing the extender on, but I only tightened it 1/2 turn past hand tight.
I ahven’t had good luck with pitstop, but any of the brands of latex sealant should be fine. DO NOT let them deflate fully while drying though, if you’re unlucky the latex might bond two walls of the latex tube inside together and then you’re in deep shizz. if you can hang it up without pressure on the tube inside that would be the best.
Ah, sorry I get what you are saying now. But is it removable on this tire? I thought the OEM valves that come with all tires are permanently mounted to the inner-tube? I dont think I have seen a tube in which you can completely remove the valve all together. Below shows the tire for a Zipp 1080, with two valve extenders and the OEM valve (gold). The leak is at the base, as indicated by the arrow. Both tires started leaking at this location after I screwed on the extenders.
I have always removed and installed a separate valve for my tubulars/race wheels…though i have been using vittoria corsa evo cx. it looks like the tangente valve cores are removable, but you’ll have to see for your specific model number. good luck.
It looks like there is not a leak I guess. At 110 PSI I loose about 2 PSI per hour. Considering the tubes are 21mm and they are cotton with a latex core, I guess that is not that far off from what I have seen on here. It gives the impression that it is leaking air because I believe the tubular is completely sealed, and so the cumulative air that leaks through the entire latex tube escapes only at the valve stem hole, giving the impression there is a puncture.
I use Caffe Latex for this issue. 35 ml injected into the tube should do the trick for you. Make sure you store the wheel with the valve at the top afterwards to keep the caffe latex from sealing the valve hole.
