Originally Posted by
gaucho777
I've been riding tubulars since the 80s and I have also experienced what [MENTION=427857]L134[/MENTION] is describing. Not often, but more than a couple times. I have submerged a tubular to find small bubbles emanating from a general area of the sidewall (say a few inches long),
A dried out casing may indeed give a false indication, but I try to touch up areas like that with latex emulsion because the bare casing is more prone to abrasion damage. In any case, pinching the tread around the bubbles should give you an idea where the damage lies.
Valve hole bubbling might indeed be displaced, but when I've had that, it was leading to an irreparable failure of the stem on some Vitt CXes.