Magical deflating tyres.

[LosingFocus]

I'd almost be beginning to wonder if someone is letting them down!

The thought had crossed my mind!

Well, the tyre was at 10psi this morning, so it had gone flat again. Will put another new tube in and try again. Still no visible or audible puncture signs...

 

[2Loose]

Cap on or off? Do try the theory on the already tested tube even if you can't see a leak. Whatever it is, it sounds like it is really, really slow...which makes me doubt a hole in the tube itself.

If it was slow puncture, it would get a little faster everytime the tube was reinflated as the hole was stretched a little bit more, so rather than replace the tube everytime without ever finding a hole or ruling out any possibilities, perhaps it would be best to stick with one until the cause makes itself known.

 

[LosingFocus]

Cap was on last night but Ive pumped it up and left the cap off this morning.

 

[Jezston]

I'd almost be beginning to wonder if someone is letting them down!

This is what I thought reading this thread!

Someone in your household not so keen on you riding a bike? Or a bit of a prankster?

 

[LosingFocus]

This is what I thought reading this thread!

Someone in your household not so keen on you riding a bike? Or a bit of a prankster?

Nope. The wife likes getting me out of the house and I'll be buggered is the 4y/o and 1y/o can open the garage door. Plus, Im sure the roadie tyres would be "dealt" with also if that was the case!

 

[Angelfishsolo]

+1

Cap on or off? Do try the theory on the already tested tube even if you can't see a leak. Whatever it is, it sounds like it is really, really slow...which makes me doubt a hole in the tube itself.

If it was slow puncture, it would get a little faster everytime the tube was reinflated as the hole was stretched a little bit more, so rather than replace the tube everytime without ever finding a hole or ruling out any possibilities, perhaps it would be best to stick with one until the cause makes itself known.

 

[LosingFocus]

Right, pumped and cap off since 7am this morning. It's flatter, say about 20psi down from around 45psi.

 

[LosingFocus]

Now THAT isnt right, is it?

 

[postman]

When you find out .How to eat something that big and then lose weight .Get a patent on it .Cos there are millions of flb out there dying to do the same .You will make a fortune and then you can pay someone to cycle for you .

 

[LosingFocus]

Errrr....

 

[2Loose]

That sort of bulge will happen if the tube isn't constrained inside a tyre. Kind of like when you blow a long balloon up, once it has enough pressure it will start to bulge in one point before the bulge spreads the length of the balloon.

45psi is a lot for just a tube...but it still doesn't tell you where the air is being lost from unfortunately. It does rule out the valve being depressed by the valve cap though. I still suspect the valve itself is leaking air very slowly, but what to do about it...

 

[LosingFocus]

That sort of bulge will happen if the tube isn't constrained inside a tyre. Kind of like when you blow a long balloon up, once it has enough pressure it will start to bulge in one point before the bulge spreads the length of the balloon.

45psi is a lot for just a tube...but it still doesn't tell you where the air is being lost from unfortunately. It does rule out the valve being depressed by the valve cap though. I still suspect the valve itself is leaking air very slowly, but what to do about it...

I didnt pump to 45psi when the tube wasnt in a tyre! The bulge was at about 10psi I guess, if that - not much air in it at all.

Ive put a new tube in now as the whole thing is doing my head in. *IF* that is OK in the morning (currently the wheel is sitting in the dinning room at 60psi) then I will also put a new tube in the rear (oh er) and be don with it all hopefully.

 

[2Loose]

I didnt pump to 45psi when the tube wasnt in a tyre!

I was wondering how it hadn't gone bang!

How many tubes is that now? Starting to wonder if (excluding the kenda) they are part of a bad batch and wondering if Zoiders has a point about Halfords valves being crap. Seems like you are having all the luck! Nothing worse than not knowing why though.

*confused*

 

[LosingFocus]

1 Kenda and 1 H/fords. A second H/fords is in the tyre at the moment.

 

[the_mikey]

Other than tiny pinhole sized punctures, I can only suggest the valve.. If it's a very small puncture, it may not release it's air when out of the tyre and submerged in a bucket of water at low pressure, but may leak when inflated to 100psi for example. Check the tyres for any glass or foreign objects stuck in the tyre wall or tread, change tyres if needed.