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I pumped my cycle front tyre to 105 psi (700*23c) 5 days back and cycled some 60 km on the same day without any punctures. Afterwards I parked the cycle in my bedroom for the last 5 days (due to security reasons I always park them in my bedroom).

Today in the evening the cycle tyre burst and I don't know for what reason. The burst occurred on the middle of the tyre and since not only the tube but also the tyre burst it couldn't be a slow puncture. The temperature in the room would have hardly reached 30 degree Celsius. I have ridden a total of about 4000 km and the tube-tyre set is from the manufacturer.

Does anyone know the reason for this and how to prevent this?

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    This kind of thing can happen. It is unusual, but not unheard of. I saw a guy's tyre go pop once as I was getting off a ferry - his bike had been sitting idle for the previous 10 hours, and all he did was pick it up. But nothing you've said is particularly unusual apart maybe from the ambient temperature - that's probably hotter than most of us store our bikes (possibly on the high side of the manufacturer's tolerance?). But why it burst today and not yesterday or the day before, impossible to say.
    – PeteH
    Mar 18, 2014 at 17:43
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    oh and I'm fairly sure there are other discussions on this subject on here, sorry do not have time right now to find them,
    – PeteH
    Mar 18, 2014 at 17:49
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    In the question heading you say the tire burst. We've all seen tubes burst, but the tire bursting is surprising. Did the tire sidewall burst, or where?
    – andy256
    Mar 18, 2014 at 20:29
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    Yes, there would be two distinct failure modes. One where the tire slipped off the rim and the tube burst, leaving the tire at least superficially undamaged, and the other where the tire itself blew out. The "slipped off the rim" thing can be just dumb luck, can be due to poor tire mounting, or can be due to a bad rim. The "just blew out" case, with a hole in the tire, is pretty much for sure due to a damaged or defective tire. Mar 18, 2014 at 22:42
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    the same thing just happened to my tire to.... i guess since i rode ma bike with less air in it,,,, i feel it might have got damaged, later on when i had pumped air, it eventually would have stretched and bust
    – user11080
    Apr 27, 2014 at 17:54

3 Answers 3

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Since the actual tire has burst, I think the most likely cause is that over the course of the 4000km you have ridden, the tire has suffered a cut or other damage that you did not previously notice.

While sitting in your room, the pressure of the tube has gradually stretched the damaged area, and then burst.

Inspect the other tire to check for cuts or severe wear.

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  • Thank you for the answer, yes, there are lots of small holes and cuts in the tyres. What shall I do for this?
    – Freakyuser
    Mar 19, 2014 at 8:55
  • The safe answer is to replace the tire. The risk is that something will penetrate the hole / cut and cause another blowout. Where I ride I (think that I) know the risks and just keep riding, but that is not advice I'd give others.
    – andy256
    Mar 19, 2014 at 10:57
  • @Freakyuser - If you ride in areas where there are apt to be a lot of hazards (broken glass, etc) you definitely should get puncture-resistant tires. These come in two varieties: "Kevlar (aramid) belted" tires, with a reenforcing "bullet proof" fabric belt around the circumference, and tires with a tough plastic layer around the circumference. The former is lighter and more flexible but the latter is probably more resistant to glass-type hazards. Mar 19, 2014 at 11:44
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I'll second that this was probably just not your lucky day and you probably couldn't have done anything reasonable to prevent it (assuming the wheel, tube itself is in good condition and the tire was properly inflated to begin with).

In the case of the ferry that PeteH mentions, the ambient temperature may have been much higher than the outside temperature. Lets consider cars. In 90 F (32 C) weather, the interior of a car can be easily 120F (49 C) - 140F (60 C). Using the ideal gas law, PV = n RT, we see that if we fix the number of air molecules (n) and volume of the tire (V) [Obviously, the tire gets a little bigger when it gets hotter, but lets neglect that], and move from pressure and temperature (P1,T1) to (P2,T2) where temperature is in Kelvin, P2 = P1 (T2/T1). So, assuming that the tire was pumped at 32 C and was left in a car and reached 60 C, its pressure would go up about 9% (so a 105 PSI tire at 32 C would be at around 115 PSI at around 60C). Still, in the ferry case (where the temperatures would likely be lower than in a closed car), most likely a case of bad luck since you can often exceed the marked maximum tire pressure (which is likely ~120 PSI for a 700x23c tire). Note that tires also heat up while riding, though, but the testing is likely for significantly higher temperatures anyway.

Here is a nice piece from the NY times which seems to indicate it might be tube conditioning or a jarring temperature effect if you pump and ride at drastically different temperatures [70F inside -> 150F roads (if the tire reached 150F, thats around a 15% increase according to ideal gas predictions]. I don't have a figure for how much a tire heats up in "typical" riding, but clearly, there is likely a significant design margin for pressure and material properties for that.

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    I recall, 30 years ago, seeing at least two, maybe three bikes laying down in a parking lot get blow-outs of the off-the-rim variety, all within 15 minutes. It was a hot day and we'd just completed a probably 30 mile morning, fully loaded. Mar 18, 2014 at 22:45
  • @DanielRHicks I wish I could remember 30 years ago!! ;) Did you maybe mention this in another post, got a feeling it might that post I was thinking of when I mentioned a dup above.
    – PeteH
    Mar 18, 2014 at 22:56
  • @PeteH Ah, he was young and impressionable then :-)
    – andy256
    Mar 18, 2014 at 23:48
  • @PeteH - Yeah, I think I've mentioned it before. It was interesting in that I got to see at least one failure as it happened -- the tube poked its head out of the tire and blew a bubble several inches across before it popped. Took probably 2-3 seconds. Mar 18, 2014 at 23:49
  • (This was my first group tour, so a lot of events stuck in my head, particularly the bra incident.) Mar 18, 2014 at 23:50
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A 700x23 bicycle tire has a finite life span dependent on:

  1. The surface damage done to the tire
  2. The distance the tire has been ridden
  3. The age of the tire
  4. The initial quality of the tire

The tires supplied on bicycles straight from the manufacturer are generally at the lower end of quality of bike tires. From my experience I expect to get 2,500 miles from a rear tire and 3,000 miles from a front tire, assuming I avoid damaging the tire with cuts from road debris.

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