gaucho777 

I've been riding tubulars for decades. Something new happened yesterday when I got a flat. The tire in question is a Vittoria Corsa CG tubular. There was a lot of glass on the road (afternoon of a trash/recycling day in a college town) and I missed in my attempt at missing some glass. I felt it under my rear tire, POP, heard the crunch of glass, and the tire was immediately deflated. I knew it wasn't something that could easily be fixed with sealant, so I pulled the tire off the rim and mounted the spare. This is when it got weird...

I started to fold the flattened/damaged tire to mount under the saddle, but it wouldn't completely deflate. I couldn't fold the tire tightly. Valve unscrewed? Check. It felt like there was still air stuck inside, but no air would come out. Maybe the valve is messed up, I wondered. Next, I completely removed the valve. Still, the tire was "partially inflated" but I couldn't get more air out. I couldn't inflate it either. I'll deal with this later....

When I got home, I attempted to repair the tubular. Again, it was really hard to inflate the tire, like I was trying to inflate a tire with the valve screwed closed. I needed to get some air in the tire to find the original puncture. I kept pumping and got to about 45 psi, when the air gushed into the tire, followed quickly by another "pop" and some crinkling noises like the tube was moving inside the casing, then a whooshing of air that seemed to come from around the valve. However, when removed the pump head, I again could not completely deflate or easily reinflate the tire.

At this point, I cut open the tire near the valve and discovered the inner tube had essentially collapsed on itself. The top and bottom of the are stuck tightly together. I'm not able to move the inner tube at all. I'm worried that another forceful attempt at inflating the tube will cause a blowout opposite the valve where the other side of the tube is stuck to the tube itself. In other parts of the tire, I can feel pockets of air that seem to be sealed by the collapsed inner tube which feels stuck to itself like a solid piece of rubber instead of a tube. It's like someone took a vacuum sealer to parts of the inner tube.

Has this happened to anyone else? At this point, I'm going to leave the tire in a warm spot (it's in the 70s here in sunny CA) and hope the tube loosens up. Failing that, I may just send it to TireAlert.com for repair. Any other thoughts, explanations, similar experiences, remedies, etc.?

woodcraft

I've seen that several times, with used tires. Sealant becomes sticky and glues the tube to itself.

Small pockets between the stuck sections burst on inflation- the pop that you heard. No fix, IMO, and a reason to not add sealant prophylactically, and to keep tires inflated if it has been added.

I've also seen glob of hardened sealant at the base of the stem, preventing tire from deflating.

Here's the remains of one:

gaucho777 

Thanks for the feedback, woodcraft. Interesting. I can see how that might happen. I've been using sealant for a while and mainly ride on tubulars, but this is the first time happening to me. I like how you say "a reason to not add sealant prophylactically." I avoid putting sealant in until I get that first flat. I don't ever remember adding sealant to this tire--only ridden a few hundred miles--but it's possible. I notice your green tube seems to be the same variety (Vittoria?). I wonder if this type of tube is any more prone to sticking to itself than others. In any case, thanks for the added data point.

woodcraft

I'm pretty sure I've seen the same with red inner tubes, for what it's worth,

but not with butyl ones.

Have you ridden the Nifty 10-50?

repechage

initial post did not mention sealant but I think that would do it.
hand drafting... uncommon today!

DiabloScott

Good reason to inflate my spare periodically too.

squirtdad

i have seen that with latex tubes with sealant that sat for a long time after being removed.

note to self: inflate the tubies on the bike I only ride once in a while.....as i put sealant in prior to flatting

woodcraft

Plan for modification to a house that I built in 1994. Same architect, so they used the original drawings.

I scratched my head for a moment about how this comment related to bike tires.

repechage

Classic & Vintage