I flatted a tubular this weekend, a Vittoria XG. It's a puncture at the stem, and I don't know if it's repairable. Any thoughts on the Vittoria Pit Stop inflator/sealant, or some other such inflator? Is there any other way to repair the tire at the valve stem? I'd rather repair it than have to remove it and re-glue another tire in the middle of the season. I'll replace it over the holidays, but 'til then, I just need a quick fix to get me through the next few races.
Are you sure it has a puncture at the stem? Frequently when a tubular punctures, the outer cotton/poly/whatever casing holds the escaping air fairly well, except at the obvious hole around the stem. A lot of air escaping there may make it seem like that is the location of the puncture, but it could be anywhere. Unfortunately, I know this too well from unfortunate experiences in this early season's racing.
Eschappe is absolutely right, that if the puncture or tear IS near the stem, the flexing from the inflating process will almost certainly reopen the damage. Not a tube that I'd use on race or any other day.
If you are not CERTAIN the damage is at the stem, and have a removable valve core (and most tubies do) open it up, put in ~1-2 fluid oz. of your sealant du jour (Stan's, CaffeLatex, PitStop, Hutchinson, whatever), put the stem back in, and giver 'er a go while rotating the tire around to help the sealant find the hole. At this point you won't do any more damage to the tube, so why not?
Pretty sure it's at the stem. It won't hold air at all, and when I try to pump it up, I can feel air rushing up from the valve hole in the rim. It's a $45 tire and I've gotten some good use from it, so frankly, I don't want to bother unthreading and re-sewing. I'll try the pit-stop and let you know how it goes. I'm not confident it will work, but it's worth a try.
The tire is shot. There's a big tear about 2mm from the base of the valve stem. Sealant just pours right out of it. I don't really know how it happened, it's behind the base tape, and not exposed to anything (ie, thorns).
And I don't know about the Vittoria Pit-stop, it's like hair mousse, same texture and odor. Not that I'd know...
FWIW - I just got a call (from my kick-ass cyclocrossing wife, see my photos) that my tires arrived back from Tire Alert with new tubes and basetape, inside of two weeks which was their estimate! I'll post photos of their work and give them a test this weekend to see the results (does the new tube take away the supple feel, does the basetape hold, is the tape on straight, etc.). I'm racing the mtb-esque course at Coyote Pt this weekend in the Bay area, so if you know the course, it will CERTAINLY test the base tape work.
Time to go home, open a belgien beer or three, and get some Mastik on the base tape. Glue them on tomorrow AM, and I'll be all set for race time on Sunday afternoon!