Tubular Troubles, a Problem Solved

Ever spend $75 plus labor to get a nice sew-up glued on to your wheel and then get a slow leak the second time out? I have. Luckily, an old buddy of mine will fix it for $15-20, depending on the tire. However, I wanted  to try to solve the problem using tire sealant. The first cut was Vittoria Pit Stop. You can find it for $10-15, depending on the source and quantity purchased. I'm afraid I may have misused it, so I'll withhold judgement. There are "instructions" on the can which consist of pictures only. A little cryptic. There is a video on youtube by Trisports and then if you read the commentary someone basically yells at them for doing it wrong, stating the can must be held upright. The only controversy is whether the device should be held upright or upside down. Bikesport Michigan is a big proponent and they have an article which indicates upright (at least going by the photos, they don't explicitly say). This jives with what's on the can. A local MTB mechanic swears it should be upside down.

So here's what I did. Started it upright and concluded that the liquid was not being delivered. Pulled it out momentarily and changed to upside down which instantly shot the liquid out and made a mess around the stem. Note that I needed a valve extender as my valve stem is only 10mm exposed, enough to pump the tire but not to push the Pit Stop canister on. I now suspect that if you stayed with the upright position that the liquid would get delivered near the end of the process. If anybody out there has used it successfully, please let me know what you did. This didn't seal the tire, but a little of the liquid was still in the device.

I then purchased a 16oz bottle of Stan's Notubes. Way more than I'll ever use. They also sell an injector (ten bucks), but I used an industrial syringe (free for me from a friend, but $1 each in boxes of 12) to put 10ml of the stuff in the tube after removing the valve core. Then I inflated the tire (Veloflex Criterium) to 120 psi and spun it around to distribute the stuff. I've heard of people using as much as 30ml in road tires (twice that in MTB) and maybe some of the Vittoria stuff was left behind, so there may have been 20+ ml of latex present. I re-inflated the tire twice more and it ultimately held. If you know where the hole is then this process is easier, you can just rotate the tire until the hole is down and the liquid runs out and seals. After wiping up some excess it was obvious that there's more to this than just latex, there's some very fine powdery stuff which probably facilitates sealing. 

In any case, I'll get the chance to try again since I'm going to be buying a wheel and tire from a friend who just doesn't want to fiddle with tubulars any more. The tire has a slow leak so I'll get another shot at repair. This time I'll just go with Notubes and try to get some independent confirmation on how to use Vittoria Pit Stop and then post again. By the way, I'll never again purchase a tubular unless its valve core is removable, and may consider adding some Notubes when it's mounted to prevent flats. Also, anyone out there who's used a similar Tufo product, please comment.