An improbable deflation

[Pat "5mph"]

So my hybrid Boris had his first outing last week, after resting (tyres fully inflated) in the spare room since the beginning of November.
Before putting an end to his holidays, I did give him a once over, new quick link chain, air top up.
Couple of days later, temperatures dropped, ice bike gets used again, while Boris wakes up with a flat rear tyre.
No probs, yesterday morning I fixed it, inner has a large rip, cannot find the culprit.
Temperatures are milder, ride him to work and back.
This morning I'm woken by a loud hiss: Boris back tyre had another spontaneous deflation while in the living room!
Inner has a big rip, cannot see what caused it.
Anyway, how did a ripped inner stay inflated all night?
And it wasn't the cat, he slept all night in my bed!

 

[MrJamie]

Strange, maybe temperature or sunlight or something, or ghosts

When you found the rip in the tube did you figure out where about round the wheel/tyre that part was? It helps if you line the valve up with a logo or chalk mark on the tyre so you can figure out roughly where the culprit is likely to be. Also look if the rip is on the inside (valve side) of the tube or the outside tyre side of the tube. I guess it could probably be something really close to weakened that just pops eventually.

 

[deptfordmarmoset]

Hmm, this sounds like 2 mysteries to me. I'd forget about the spontaneous deflations first and concentrate on the rips. The only rips I've ever had were when the tyre wasn't seated properly on the rims and when I've damaged it pinching it with levers when the tyre was too hard to get back on by hand. A little air in the tube helps against the 2nd possibility - it sits inside the tyre better and resists getting trapped between tyre and rim.

 

[Pat "5mph"]

Thanks for the suggestions.
@MrJamie: yes, it was the first thing I did. The rips are both on the inside - valve side.
Changed the rim tape that came with the wheel for a better quality one I had bought a while ago for another bike.
@deptfordmarmoset: you could be very right
Tyre in question is a Marathon original, that I had fitted before the first deflation
by brute force, breaking a lever.
Second time round, I didn't inflate the tube a bit first, fitted it out of the box. Still, how did it survive the trip to work and back only to deflate much later when stationary?
Now the bike is standing in the living room, after today's commute.
We shall see if it's still inflated in the morning!

 

[RWright]

I had this happen to me because one of my tires was off a little on one of the sidewalls, by off I mean not manufactured correctly. I knew it was a little weak in that area but rode it anyway. I got a puncture in that tire and when I changed the tube it popped again just a few hundred yards down the road. I pushed it home and put in another tube and inflated it. It popped while I was looking at the long rip in the other tube.

I had checked the inside of the tire and the rim several times and found nothing. I noticed the rip was near the weak area on the tire bead. I had not double checked that the tube was all the way inside the bead and noticed on the third try that when I went past the weak area on the tire while checking the tube/bead that it would slide back out. I did it again and checked the weak area last and inflated and had no more trouble. I finally got rid of that tire but it was still rolling fine when I changed out my tires. I now triple check the bead on both sides of the rim before I inflate, even roadside. It may take a few minutes more but it may save you a lot more than that.

 

[Globalti]

You've checked that the rim tape is seated properly and the tube isn't herniating into the nipple holes? Also that there aren't any bits of swarf around that area?

 

[Pale Rider]

Loose spoke?

 

[youngoldbloke]

Had this happen to cheap low quality tubes (supplied by the NHS in a wheelchair tyre!!!). When inflated outside the tyre the tube looked like a string of very misshapen sausages. False economy.

 

[summerdays]

Are you trying to keep Boris nice and warm near a radiator? If so maybe when the heating came on in the morning it caused the inner tube to try and expand, whereas when you were riding it outside it was much colder so less pressure on the inner tube (if I have misunderstood physics completely please be gentle with me ).

 

[Deleted member 1258]

I'd be looking for a burr on a spoke hole, a piece of swarf, a faulty inner tube, are the tubes all the same make? Or a damaged or faulty tyre, problem with the sidewall or bead?

 

[Psycolist]

If this wasnt our sober citizen Pat, I would blame the spirits. I've had a tube apparently overinflate itself. At a point in the day I dismounted my old wreck of a bike, lent it against the wall of the house I was visiting, and as I opened the gate, I heard my tyre making a noise like it was being inflated, and then explode. I later realized that my tyre had developed a split in the sidewall, and I assume the whooshing noise was the tube expanding through the split and then bang. As the bikewas already a wreck, I rode it home on the flat, carefully though,

 

[Psycolist]

As per previous post, I didnt lend the wall my bike, I leant it !

 

[Boris Bajic]

It was the Puncture Fairy.

She is a bully and a mean, mean cow. She has no pity and no sense of humour and she smells.

She has never had an original thought and she votes UKIP.

I hate the Puncture Fairy and despise the fact that she brings no benefit to mankind.

I do not fear her. I could kick her sorry backside with one leg tied behind my back... if that makes any sense.

Carry on.

 

[Pat "5mph"]

I had this happen to me because one of my tires was off a little on one of the sidewalls, by off I mean not manufactured correctly

You've checked that the rim tape is seated properly and the tube isn't herniating into the nipple holes? Also that there aren't any bits of swarf around that area?

Had this happen to cheap low quality tubes (supplied by the NHS in a wheelchair tyre!!!). When inflated outside the tyre the tube looked like a string of very misshapen sausages. False economy.

I'd be looking for a burr on a spoke hole, a piece of swarf, a faulty inner tube, are the tubes all the same make? Or a damaged or faulty tyre, problem with the sidewall or bead?

Evening all!
Update: rode Boris to work and back yesterday and today with no more deflations - touch wood!
What I did: changed rim tape, changed batch (and make) of inner tube, triple checked tyre seating in the rim.
Had noticed that tyre having a bit of a bump in the sidewall when first fitted new, will move it to the front (quick release wheel) ... just in case
Now that is has been mentioned, all deflations I had in 18 months have been while using that batch of inner tubes. My other bikes, that took more abuse than Boris but have a different made of inners fitted have been ok.
Thanks all for the input: Boris sleeps near a window @Summerdays (no radiator)

 

[fullcycle]

Punctures/deflations are sent from a higher power unbeknown to us mere mortals