Exploding Tube

bsharp77

Hi guys,

Just done the Castle 100 sportive yesterday, as I was approaching the finishing line, there was a massive bang and yup, my front tube gave up the ghost (better then than halfway through i suppose!).
I thought perhaps the tube was maybe nipped in the tyre, but i've been running them for a month with no problems, out every weekend - seems like a long time to hold on before going bang.
The only other thing I can think of, was after 50 miles or so, i could hear a bit of modulation when braking - as if the wheel was slightly out of true - would this distort enough to make the tube pop??
Any advice much appreciated - might leave the whole bike down to the LBS to give it the once over anyway.
(the tubes were continental, the tyres are conti GP4000)

Well done to everybody who rode yesterday - first sportive ive been to, and was amazed by some of the bikes rolling out of the car park - it was better than browsing in any bike store!!

Pross

It's not uncommon for a tube to 'explode' from a sudden puncture at high pressure especially if the object that causes the puncture doesn't stick in to reduce the rate the air leaves at.

gryfon23

Did it fail around the valve or elsewhere on the tube?

Many things could have been working their way into the tyre/tube over that time and result in a sudden failure.

Pumpkin Positive

Is it possible your tyre bead wasn’t seated properly on the rim? This might also explained the ‘out of true’ feeling on the wheel as the tyre bulges slightly.

If the tyre isn’t properly seated the tyre can suddenly pop off the rim and the tube will burst. It can be pretty dramatic.

ddraver

If the tyre wall isnt ripped or damaged, I'd agree with pross, just a particularly big bit of stone/glass/metal that cased a big hole but had worked itself out of the tyre again by the time you'd rolled to a stop.

If it doesnt happen again i'd just put it down to bad luck and be thankful you werent just about to cream your mate in the final sprint!

robbo2011

Happened to me too. It was towards the end of a 100km ride whilst climbing, and suddenly the front tube went off like a gunshot. very lucky I wasn't descending at the time.

I could not find any cause, the front tyre was free from sharp objects. Just one of those things.

Lycra-Byka

Pumpkin Positive wrote:

Is it possible your tyre bead wasn’t seated properly on the rim? This might also explained the ‘out of true’ feeling on the wheel as the tyre bulges slightly.

If the tyre isn’t properly seated the tyre can suddenly pop off the rim and the tube will burst. It can be pretty dramatic.

I'd go with that.

Op.
Was it under heavy breaking it happened?

bsharp77

Hi guys, thanks for all the replies.
Lycra - no, not under heavy braking, I was just soft pedalling towards the finish line, and heard the massive bang - funny thing was I didnt even realise it was me for a few seconds!!
Im going to have a close look at everything tonight - will inspect tyre and tube, and see how it goes when I put a new tube in - but as mentioned, the tyre & tube had been fine for weeks, so maybe it just was a random puncture - sounds exactly the same as robbo described.
Ill update tomorrow with more info - thanks again for the responses everyone.

keef66

It's never happened to me and I'm having trouble imagining a tube going bang when it's inside an intact tyre. I've always thought that if a tube explodes it means it's found some way out of the tyre, ie a bead slips off the rim ,or a large hole is made in the tyre.

I'm waiting for your forensic investigation with curiosity...

Sharkyssurfers

I had that not long ago, put it down to me possibly over inflating the tyre, i had the same symptons a rubbing vibration and then 10 miles later POP, blew the tyre of the rim as well!

thegreatdivide

keef66 wrote:

It's never happened to me and I'm having trouble imagining a tube going bang when it's inside an intact tyre. I've always thought that if a tube explodes it means it's found some way out of the tyre, ie a bead slips off the rim ,or a large hole is made in the tyre.

I'm waiting for your forensic investigation with curiosity...

Does this not happen a lot on long descents e.g. the Alps on clinchers? Your rim heats up, in turn heating up the inner tube then 'BANG!!!'. My mate's other half had a double blow out on a descent from too much breaking. Could have been nasty but she just scared the life out of some cattle

bsharp77

Hmmmm, I see im not alone! Just home and going to have a look at the tyre soon, so will report back later - but just for reference, I pump the tyres to around 110psi - which is what my LBS recommended....they've always been fine up till now.
The comment about heavy braking is interesting - there was a lot of up and down on the course, and as Brad would say - i descend like a bit of a girl, so was squeezing the levers tight quite a lot! But in fairness, the bang happened at the finish, long after any descent, so any increased rim temperature would have been long gone I would have thought....??

thegreatdivide

I came off a long descent where I was doing quite a bit of breaking (no shame in that) and I touched the front rim while waiting for some mates at the bottom. Nearly took the skin off my fingers! :shock:

dennisn

Pumpkin Positive wrote:

Is it possible your tyre bead wasn’t seated properly on the rim? This might also explained the ‘out of true’ feeling on the wheel as the tyre bulges slightly.

If the tyre isn’t properly seated the tyre can suddenly pop off the rim and the tube will burst. It can be pretty dramatic.

I'm going to cast my vote with "Pumpkin Pos". Especially the part about it being "pretty dramatic". I actually happened to see a tire come unseated on my front rim. Seemed to happen in slow motion until the "big bang", which was much louder than any puncture I've ever had.

bsharp77

Good evening fellows...
Well my forensic examination is complete - and I have photos!

So, took the tube out to have a look, and found a lovely hole which screamed "spoke pushed through" (as it was on the inside of the tube) - I present photo no.1:


Finding nothing wrong with the rim, i proceeded to put in a new tube and inflate....look what I found:


And heres a close up of the tyre where it failed:


So im guessing from all this, that the tyre was failing gradually, which explains the modulation i was feeling while braking throughout the ride- and eventually it gave way enough for the tube to pop out a bit and cause the massive explosion! (although I have to say, its an incredibly small little hole for such a loud noise - last time I had a tube go off like that it was ripped to shreds!)

Do you think this is a tyre manufacturing fault?? Certainly looks like it to me as its failed on what looks like a stitched seam - however I bought the contis from bike-discount.de, so it would be a real pain to send it back - ill maybe contact conti direct and see what they think. (tyres are less than a month old)

Either way, its onto wiggle tonight to get a replacement in time for saturdays ride....hopefully they will give me some Haribos to cheer me up!

earthvspace4XTuUWcX

Is it possible that your brake block was rubbing on the tyre and eventually caused it to fail?

bsharp77

Ahhhh, thanks xdoc - I had a quick look this morning - and guess what.....the brake pads are slightly high looking - but whats worse is the whole brake unit itself is a little bit loose and hanging slightly to one side (more of a gap between the pad on one side of the rim than the other) - i can easily push it side to side.

So looks like the main brake hanger needs a good tighten, the pads need realigned against the rim and all should be good - new tyre on the way from wiggle (a lot dearer than bike-discount.de, but im in a hurry)

Thanks to everybody who left a comment - one of those things I guess - ill have to keep a tighter eye on such things from now on!