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I have a mountain bike and just replaced the tires and inner tube. The tires recommend up to 65 psi. When we hit about 55... the tube popped. Is the issue likely the tube... or could the tire have an issue that caused the tube to pop on inflation?

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  • It could be either. It could be neither. Other possibilities include the rim tape and getting the tube caught in the bead. Tell us more about the nature of the puncture. If you try again with a new tube does it fall at the same place with respect to the wheel? With respect to the tyre? – Chris H Aug 24 '17 at 16:27
  • Where and how did the tube pop? The answer to your question lies therein. Additionally you have the wheel or improper installation as culprits. – Deleted User Aug 24 '17 at 16:52
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    Take out the tube and find out how it popped. My guess is that you pinched the tube under the bead of the tire, or you had the valve not be free. My guess is probably user error. – Batman Aug 24 '17 at 17:12
  • Did the tube bulge out and go bang. If so possibly the tire wast not seated properly. – paparazzo Aug 24 '17 at 17:56
  • Is the hole on the tube a C shaped flap, a straight line tear, or a small pinprick? And did you check the tyre inside for any possible cause. Even new tyres can have sharp stuff in them. – Criggie Aug 24 '17 at 20:54
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This has happened to me on occasion (especially if I bought a cheaper tire). Mark the tire and rim before dis-assembling the wheel. Any temporary marking will do. When re-assembling the tire line up the tire/rim marks. If the tube pops in the same, or near, place - then it is (most likely) the tire.

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I assume that when you say popped you mean it flatted etc. But unless the tire came off the rim, it is unlikely to be the tire. But check the inside of the tire for anything that could puncture the tube.

What I do is to mount the tire with the label/logo at the valve. That way when I remove the tire and find the puncture I know where to look on the tire for a nail or whatever.

The way I mount a new tire is to stuff the tube in the tire. Inflate it just enough so it has form with no folds. I get one side over the rim all the way around. This is usually quite easy. I then make sure the tire is in the rim. Finally, I start at the valve and work the other bead in to the rim. I do this all by hand although I understand some tires are tight enough to make this pretty hard. You might want to get a tire jack if that is the case instead of trying to use tire irons.

While in this barely inflated state, I work around the entire wheel sort of pinching / flexing the bead to make sure it is seated. Then I pump up to about 1/2 pressure and bounce the wheel at various points.

Lastly, I deflate the tire to relax the tube and let it do any final shifting it wants to do and then inflate to the desired pressure.

Sounds like a lot of work but it really is but a minute or two.

BTW most tires show a max pressure but that isn't necessarily the pressure you want. Like an auto, you'll want the best contact patch which varies from tire to tire and with the total weight.

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  • It can very easily be the tire, either due to a large hole in the tire or a damaged bead. (Not to mention a piece of metal embedded in the tire tread.) – Daniel R Hicks Aug 27 '17 at 18:16
  • But a common cause of repeated flats is using metal "tire irons", or, worse, screwdrivers to mount the tire. – Daniel R Hicks Aug 27 '17 at 18:16
  • That's a strange way to mount a tyre. Unless you're replacing the tyre itself, there's no need to take the tyre right off the rim. Just take it half-way off, then put the tube in, partly inflate it and put the tyre back on. Putting the tube in the tyre with it completely separate from the wheel just seems like an extra opportunity to pinch the tube against the rim. – David Richerby Aug 27 '17 at 22:10
  • It's a lot easier to check for the sharp object in the tire when it is off the rim. – WLindsay Aug 28 '17 at 20:43

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