Inner tube blown ?

Adam4868

Guru
After a ride yesterday on the way home I hear a rubbing noise.Bit like Tyre on mudguard or a brake rubbing.
Thing is no mudguards and disc brakes.So I think I'll pull in through the lights when Bang ! Back wheel flat.Took Tyre of and there's a two inch tear in the inner tube ? New tube in and on my way.
I took the bike out today and seems ok,couldn't see any defect in the Tyre.Is this just a bad tube ? Or any thoughts.
 

Ajax Bay

Guru
Location
East Devon
Tube has crept out under a failing side wall / bead, probably. Has the tyre distorted, hence the rubbing noise you heard?
 

raleighnut

Legendary Member
Surely a tube doesn't go bang and get a big rip unless it is unconfined (eg poking out of a hole).

If it's confined within the tyre it will go hissss and have a smaller hole - or small cut in the case of a snakebite.

On that basis I would doubt that it was the tube alone. It must have got out somehow in order to pop.

Of course, being an idiot, I could well be using flawed logic there.
Nah I'd say it had popped out too.

@Adam4868 had the tyre gone a bit 'soft' feeling prior to the bang.
 
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Adam4868

Adam4868

Guru
Thanks,I rode the Tyre today for 20 miles and checked again tonight seems ok.Cant see any damage to sidewall or tread.Seems to run pretty true.Its a newish Tyre,probally 300 miles at most
 
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Adam4868

Adam4868

Guru
The only thing I noticed is it was a wired Tyre and tight enough to get on when bought,seems to have a lot of slack now and a doddle to get back on
 

Smokin Joe

Legendary Member
Thanks,I rode the Tyre today for 20 miles and checked again tonight seems ok.Cant see any damage to sidewall or tread.Seems to run pretty true.Its a newish Tyre,probally 300 miles at most
You say it was a newish tyre. Now I had a similar problem once at about the same mileage on a new bike. a long snakebite puncture on the tube. Fortunately it did it's stuff in the garage overnight, but the tyre had never been off the rim while I had it and I can only conclude that the tube had been slightly nipped the bead on fitting at the factory and then failed eventually rather than soon afterwards.
 

bikingdad90

Veteran
When you take the tyre off, have a look for excess rubber round the beading edge. I had a tube blow the bead off a rim under inflation with the track pump as it wasn’t seating properly due to some excess rubber. Made one heck of a bang and I had ringing in my ears afterwards.

I now always make sure I pump tyres up to max pressure and then release back down to desired pressure making sure I hear the click so I know the bead has sealed on the rim.
 

rogerzilla

Legendary Member
Most tyre beads stretch a bit (permanently) when inflated on a rim, especially folding tyres, so a tyre that was nearly impossible to fit can be removed without tyre levers a couple of weeks later.

The tyre popped off the rim and then the tube exploded. There are only three common reasons for a tyre popping off:

1. Tube trapped under bead (go round both sides of the tyre and check for this before inflating it, especially if it was a struggle to fit)
2. Gross overinflation. However, I know Schwalbe Duranos can blow off at only 10-15psi above the maximum pressure (which is surprisingly low for a 23mm tyre).
3. Damaged components, e.g. rim splayed from hitting a pothole or a badly kinked wire bead.
 
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Adam4868

Adam4868

Guru
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