Mysterious flat...

[steinspinne]

So I haven't ridden in about a week. Yesterday was absolutely beautiful so I decide I'm going to ride to work. I get dressed, go to the kitchen to retrieve my bike, and notice my front tire is completely flat. No air whatsoever. Bummer.

Today I take out the tube and grab my patch kit, pump a little air in the tube and listen for a telltale hiss... nothing. Not a single little pinprick. I run my fingers along the inside of the tire, nothing suspicious. Very peculiar.

Have any of you experienced this before? Now I can understand needing a little boost, I usually have to add 40-60 psi before each ride, but completely flat? It boggles the mind. I'd really like to know what caused it so I'm not caught after class with a flat. (I know I need to invest in a frame pump, just don't have the funds at the moment.)

[bike4ever]

Over inflate your tube. Small pinch flats can be difficult to find at times. Also with the tube inflated, put it in water - you'll see the hole by following the air bubbles.

[Eden]

if you can find no holes, it could be a broken/leaky valve

[spokewench]

You undoubtedly have at least what you call a "Slow Leak". Sometimes, they are slow enough that they don't bother you while you are riding but left over night or a a couple of days and the tire will be flat.

There is something causing this, so you should probably try putting it in water to find the telltale bubbles where it is leaking. Fill the tube with air, put it in a bucket and squeeze on the tube to find the bubbles if they are not apparent right away.

My hubby has been known to ride for miles on Slow Leak tires (he airs them up before he leaves each time). Me, I just find the leak and patch it or change to a new tube.

spoke

[BleeckerSt_Girl]

I had the same thing happen this weekend. Turns out there was a slow leak where the valve connects to the rubber tube. It didn't leak unless I tilted the valve slightly. It showed up in the underwater treatment. Had to throw the tube out. Probably happened while tilting the valve out to fix a puncture in the tube.

[steinspinne]

Thanks to everyone for the suggestions! I tried the underwater treatment, and found that there was a not so small rip where the valve stem connects to the tube. It didn't leak unless I moved the stem, but when I did it was flat within seconds. Ran to the LBS to catch them before close and got a new tube.

Thanks for the help!