Strange Reacurring flat tyre

[Shivington]

I pump up my front tyre and a couple of days later it is flat. So I took the tyre off removed the inner tube checked for puncture, which I couldn't find, I had a new inner tube so replaced it anyway.

I pumped up my old inner tube and left it to one side and it's still inflated, so no puncture right?

Went to my bike today with the new inner tube in and the tyre is flat again! I'm so confused as it definitely don't have a puncture as shown by the old inner tube still being inflated. What could it be ? I'm perplexed . Thank you

 

[Deleted member 1258]

At a guess some strange valve problem? Pump it up immerse the valve in water and look for bubbles.

 

[Shivington]

Thanks Dave I've done that on both inner tubes the old and new one and both are fine no bubbles to report . Could it be down to the acruel tyre itself do you think?

 

[numbnuts]

Puncture fairies there a bugger to get rid of

 

[jonny jeez]

Check the rim tape, it may not be anything to do with debris in the tyre but rather a nipple pushing against the tube from the inside.

edit, sorry just realised you had a "contirol tube".

check the dust cap you put on, any debris inside that, that could put pressure on the valve release?

 

[welsh dragon]

I have kenda puncture resistant tyres with Kevlar rims. My back tyre went flat a couple of times. I thought it might have been a faulty valve. There were no bubbles from it though. After pumping the tyre up a couple of times it seems to have cured itself. Thank God. Good luck. Hope you find the problem and can fix it.

 

[Levo-Lon]

As its occurred with both tubes id say its a very fine sharp doing the damage.
the difference with an insertad tube is it has high pressure s deflates and goes soft.
the inflated tube on its own will have only a few psi so a pin hole wont lose a lot of air.

take the tyre off and tun it inside out..check it thoroughly with your fingertips..

then thoroughly check the rim..especially where the tube valve goes.

 

[Deleted member 1258]

Thanks Dave I've done that on both inner tubes the old and new one and both are fine no bubbles to report . Could it be down to the acruel tyre itself do you think?

I doubt it would be the tyre itself, its posible there might be a very small piece of debris in the tyre, just enough to cause a pin hole, the tube will stay up below a certain pressure

 

[Shivington]

Thanks everyone @numbnuts sure my dog is sneaking in there and deflating it so I can't go out!!.

I guess it's going to be a case of taking the front wheel off again and double checking it was such a pain to get off last time. Hopefully I can get to the bottom of the issue

 

[r04DiE]

As its occurred with both tubes id say its a very fine sharp doing the damage.
the difference with an insertad tube is it has high pressure s deflates and goes soft.
the inflated tube on its own will have only a few psi so a pin hole wont lose a lot of air.

take the tyre off and tun it inside out..check it thoroughly with your fingertips..

then thoroughly check the rim..especially where the tube valve goes.

^^Agreed. You could also try putting a good bit of air in the tube (but don't go mad) and then submerging it, a section at a time while you look for bubbles.

 

[Milkfloat]

Have you annoyed someone who is letting down your tyre?

 

[ColinJ]

I doubt it would be the tyre itself, its posible there might be a very small piece of debris in the tyre, just enough to cause a pin hole, the tube will stay up below a certain pressure

I reckon Dave could well be right - I had one of those punctures once. The tyre kept going down over a week or so but I couldn't find the hole. I held the semi-inflated tube under water - no bubbles!

In the end I went round the tube stretching all parts of it under water and eventually discovered the tiniest of punctures. If I didn't stretch the tube, it didn't leak. As suggested above - pressures are much higher when tubes are inflated inside tyres.

There was a minute shard of glass in my tyre. The only way I found it was by seeing how far the hole in the tube was from the valve and examining the corresponding part of the tyre.

 

[Deleted member 1258]

I reckon Dave could well be right - I had one of those punctures once. The tyre kept going down over a week or so but I couldn't find the hole. I held the semi-inflated tube under water - no bubbles!

In the end I went round the tube stretching all parts of it under water and eventually discovered the tiniest of punctures. If I didn't stretch the tube, it didn't leak. As suggested above - pressures are much higher when tubes are inflated inside tyres.

There was a minute shard of glass in my tyre. The only way I found it was by seeing how far the hole in the tube was from the valve and examining the corresponding part of the tyre.

In my case it was an old patch that had started to fail, the tyre wouldn't hold full pressure, but wouldn't go down either, it would just go soft, I put a fresh tube in then took the old tube and pumped it up as much as I dared and gave it the water treatment, spotted some bubbles coming from the patch and on closer inspection discovered the tube had started to split at the site of the puncture.

 

[shouldbeinbed]

Could be a stray wire in the tyre, ride it, the tyre flexes, the wire pokes up and tiny pinprick puncture, take the tyre off, the offending bit is lying down looking all innocent and inoffensive. +1 @meta lon, I'd get the tyre inside out and flex it about.

 

[bonsaibilly]

Lots of very confused answers here!!

If I'm reading this right, both inner tubes have gone flat when mounted in the tyre and inflated. That suggests on the laws of probability a problem with the tyre or wheel and not either tube.

Check tyre itself for sharps stuck in the inner wall, and also check the internal rim of the wheel, especially the joint, I had a wheel that's joint wasn't totally flush, punctured continually, sanded the sharp edge off the joint, problem solved.

Bb