What would cause a temporary loss of air??

Here’s the tl,dr:

tire was losing air - could hear it leaking and it was at about 15 psi   

Filled it up, put on trailer, and it’s held air since then  

what gives???

came off track, after about 10 minutes I noticed my left front tire was really low.  I went over and could hear air escaping.  

I went to get the compressor and a friend said it wasn’t the valve stem.  

I listened around and couldn’t discern from where it was coming  

Pumped it up, loaded on trailer and it hasn’t lost any air since then.  Even drove around town  

facts:

It was a very hot day. 

New wheels and tires and tpms/valve stems. 

Cant find anything in the tire

cant find any cracks on wheel

valve stem seems fine.  

I asked my buddy if he felt the valve stem for leaks and he said he just listened.  So, stupidly, none of us actually put our finger on it.  But at home I depressed the core a little and it was clearly coming from valve stem. 

I did not verify that it was still leaking after I refilled and moved it. 

Nothing happened on track that was of any note (no wheels dropped, didn’t even get on rumble strips)

I hadn’t noticed anything on track but the last 2.5 mile cool-down lap was done at very reduced speeds. 

obviously something was leaking....  heat-related??

crack in wheel that is sealed up?

aaarrrrgghh!!

I’ve had that happen on car and scooter tires.  Best I can figure is somewhere along the bead wasn’t sealing up properly, but the combination of losing air then refilling it caused the bead to seal.

Or there's a puncture or bead leak that only leaks in one specific position due to the way the tire is distorted in that position.

Probably a bead leak.  Have someone drive the car forward slowly while you listen.  See if the leak becomes audible at a certain point in the tire's rotation.  

Ive had it with separated plies.  Only leaks in one position.  If a bead-reseating doesnt fix it I would replace the tire.  

Aaaahhh. I bet it’s the bead.  I mounted these and this was the first one I had mounted.  It had been decades since I had last used a tire machine and we never had low profile tires like today. 

I messed up the bead a little and must not have got it seated back properly. 

Ill take a look when I have a chance.   

But thanks!!  I’m gonna Check that one off as mystery solved

Heh also came to say "bead leak"...usually they happen on cars that have been parked in one place for a long time.

Interesting. I had something like that happen but never figured it out. Thanks GRM!

Soapy water will solve the mystery. 

I had a crack in a mud tire sidewall one time that would only leak when it bulged at the bottom on the way around or when it was parked with the crack at the bottom. Anywhere else it didn't leak.

D2W said:

I had a crack in a mud tire sidewall one time that would only leak when it bulged at the bottom on the way around or when it was parked with the crack at the bottom. Anywhere else it didn't leak.

Same here. Not a mud tire, but a Michelin. 

Small leak and weak valve?

Tire leaks slow until pressure doesn't hold valve closed?

Break down  the tire, and clean up the wheel, bits of rubber and debris can cause  a bead leak.  As said above, soapy water should find it.

As a broke a$$ college student i had this same problem found out it was a nail in the tread it would only leak if the nail was parked on the tar if it wasn't it sealed.  Took me a while to find it as it was a small diameter head.  Over the course of a month the leak got worse as the nail got worn down...It became a monthly thing to push the next bigger nail in.... until the tires had no tread.   Yes i know a snot covered rope would have worked, but nails were free. I marked the side wall and made sure to not park with it down.

Getting hit in the diaphram can do it, too. 

I took a tire in to a shop for a slow leak once. They inspected it, found the leak, dismounted the tire, emptied out the dirt that had gotten stuck in the bead and gave it back to me, no charge. I slipped them a $20 anyhow.

If the rims have seen salt, sometimes some corrosion and pitting can happen where the tire mounts. Getting rid of the pitting and tapering/feathering the metal with a bit of sandpaper works wonders.

I just came in here to say I read the thread title as "What would cause a temporary loss of hair??"

I can think of few things.  Most of them family or job related.