# Slow puncture mystery



## Danny (4 Nov 2007)

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.


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## bonj2 (4 Nov 2007)

Dannyg said:


> 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?


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## bonj2 (4 Nov 2007)

Dannyg said:


> Any theories?



Warped tyre?


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## Danny (4 Nov 2007)

bonj said:


> 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.


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## Jacomus-rides-Gen (5 Nov 2007)

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".


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## Elmer Fudd (5 Nov 2007)

Jacomus-rides-Gen said:


> 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 !!


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## dan_bo (6 Nov 2007)

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..........


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## Danny (6 Nov 2007)

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.


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## spire (7 Nov 2007)

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?


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## Tynan (7 Nov 2007)

spire said:


> 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 ...


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## Amanda P (7 Nov 2007)

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.


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## Tynan (7 Nov 2007)

as if anyone needed another reason not to go to yorkshire


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## Danny (7 Nov 2007)

spire said:


> 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.


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## inaperfectworld (25 Nov 2007)

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


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## cyclebum (26 Nov 2007)

Uncle Phil said:


> 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


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## buggi (26 Nov 2007)

did you fill your tyres with a CO2 cannister when you were out? they deflate over 24 hours because it's thinner than air so leaks out. you need to reinflate with air when you get home.


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## yenrod (26 Nov 2007)

When 1st got the 1st bike ever, offthepeg (I'd built up all bikes I ever had) it had michelin dynamic tyres on. Not bad, pretty grippy, bit heavy on the feel: had the opinion they would have made good touring like tyres. 

Anyhow, time went by and I got 'slow puncture after slow puncture, after slow puncture: I was getting REALLY seriously irritated ! You know when you start off then you may get a punc. say 10mls in...so you've gotta stop, do the biz - then kick-off *again* and say it'd happen _again_ (at some mileage later)  I even wondered if someone had jinxed the bloody things..

So changed to Michelin Oriums.

Which simliar in tread pattern and very affordable.

One reason I feel tyres puncture, is that they are *not* inflated properly


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