Slow puncture mystery

[Danny]

My front inner tube developed a slow puncture this week - by which I mean that it took about 24 hours to deflate.

This morning I decided I would try to track it down, and inflated the inner tube and ran in through a tub of water. No sign of any tell-tale bubbles from anywhere on the tube or around the valve, so inflated it some more, and then some more, and then some more...until bang the whole darn thing exploded.

Never once saw any sign of bubbles even when it was inflated to a really high pressure. I've had even slower punctures which have always shown up.

Any theories?

Incidentally, how puncture resistant should I expect puncture resistant tyres to be? in August I fitted some Michelin 28mm tyres that they claimed were puncture resistant and have averaged about two punctures a month since then - which is more than I managed with my ordinary old tyres.

 

[bonj2]

My front inner tube developed a slow puncture this week - by which I mean that it took about 24 hours to deflate.

This morning I decided I would try to track it down, and inflated the inner tube and ran in through a tub of water. No sign of any tell-tale bubbles from anywhere on the tube or around the valve, so inflated it some more, and then some more, and then some more...until bang the whole darn thing exploded.

Did it shower water everywhere?

 

[bonj2]

Any theories?

Warped tyre?

 

[Danny]

Did it shower water everywhere?

It was fairly spectacular - it showered bits of rubber everywhere, and made such a load bang that the rest of my household rushed into the room to see if I had blown myself up.

 

[Jacomus-rides-Gen]

2 a month! Where do you ride!

I have 23mm Michelin Pro2 Race tyres and have so few problems - in a year of commuting through London 14miles a day I only had 4 "deflation events".

 

[Elmer Fudd]

2 a month! Where do you ride!

I have 23mm Michelin Pro2 Race tyres and have so few problems - in a year of commuting through London 14miles a day I only had 4 "deflation events".

You need to copyright that phrase JrG, so much better than the pee word !!

 

[dan_bo]

Dan, do you ride in the gutter cycle lane or do you assume a so-called 'primary position on the road? I find i get far fewer punctures than I used to and drivers are far more aware of me..........

 

[Danny]

I don't ride in the gutter York has some good cycle lanes and I use them when available - otherwise I'm either in the primary position or going down the middle of the road overtaking cars caught in traffic jams.

However as it happens all but one of the punctures on my "puncture proof" tyres have occurred when I have been out riding in the country.

 

[spire]

Assuming it was a Presta valve. is there any chance you hadn't tightened it when it was on the bike, but did tighten it when you immersed it?

 

[Tynan]

Assuming it was a Presta valve. is there any chance you hadn't tightened it when it was on the bike, but did tighten it when you immersed it?

sounds right

and blowing up inner tubes too high outside of the tyre isn't a good idea

granted you know that now ...

 

[Amanda P]

Every hedge in Yorkshire is hawthorn or, worse, blackthorn. Especially this time of year, every farmer in Yorkshire is out thrashing his hedges with a flail mower, leaving a carpet of deadly thorns in his wake.

"Cleer 'em oop? Naw, ah never bother, lad. T'cars sweep 'em all to t'side enyways".

Nothing is going to save you from a pu... er, catastrophic deflation event once an inch-long (really!), needle-tipped blackthorn spike attacks your tyre.

Hawthorn's worse - the thorns are smaller and blunter, but they go in and then snap off so you can't see them. (They do the same in your thumbs...) Only the tip of the spike remains, protruding inwards from the tyre into the tube. You may not know you have a thorn in your tyre at all until it works loose again days later, releasing the air.

 

[Tynan]

as if anyone needed another reason not to go to yorkshire

 

[Danny]

Assuming it was a Presta valve. is there any chance you hadn't tightened it when it was on the bike, but did tighten it when you immersed it?

No chance

But I guess those Yorkshire hedges could be causing the punctures.

 

[inaperfectworld]

i had a slow dfeflation and it was the presta valve but it took me a while to realise, because the bubble appeared very very slowly

 

[cyclebum]

Every hedge in Yorkshire is hawthorn or, worse, blackthorn.

You don't need to go to Yorkshire for this problem, just cycle down a canal towpath, all my defaltion experiences occour there. My last one I actually saw the offending hawthorn twig on the path but I was over it before I could do anything, seconds later I was tackling my first ever emergancy repair which I was so proud , except I forgot to remove the thorn but luckily deflation didn't occour until I was back home