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Replacing my inner tube, I've been having some trouble getting the tire back on the rim with the bead completely even throughout. For an example of what I'm talking about, see this segment of a tutorial:

(7:30-8:45)

The tire bead isn't very far up or down where it's uneven, but there's still a handful of spots it's uneven after inflating. It looks pretty good and I've been inflating/checking/deflating/shifting/repeating many more times than I remember having to last time I did this.

How important is it that the tire bead is even along the rim? What are the issues that could arise (or rather deflate) due to unevenness?

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    How badly do you want the tire to stay on the rim? A little variation -- on the order of a millimeter or so -- is OK, but when you get to 3-4mm then you're looking for trouble. – Daniel R Hicks Nov 8 '16 at 2:08
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    Note that a common problem is to get the thickened area of the tube near the valve "trapped" by the tire bead, preventing the bead from settling into place near the valve. The solution here is to deflate the tire, press the tube valve most of the way into the rim, and then work the tire bead down into the rim around it. – Daniel R Hicks Nov 8 '16 at 2:10
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    And with a new tire I like to inflate the tire most of the way, ride it 100 feet of so, then (more importantly) deflate it most of the way and "walk" it about 20 feet. Then inflate fully and check. – Daniel R Hicks Nov 8 '16 at 2:13
  • @DanielRHicks Already got through the valve "trap" finding that tip elsewhere, just keep coming up with high and low spots elsewhere. I didn't try giving it a short ride/walk though so I'll give that a go tomorrow and see how it looks – cr0 Nov 8 '16 at 2:52
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    It's a sudden blowout. And sometimes the tube pops out of the tire and wraps itself around the axle, causing the bike to stop rather abruptly. – Daniel R Hicks Nov 8 '16 at 3:13
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An uneven bead can indicate the tube is trapped under the bead. This can cause blowouts or pinch flats. Let the air almost all out of the tube until you can push the tire back away from the bead, then push the tire back from the bead and look all the way around on both sides to ensure the tube is not under the bead, but instead all the way inside the tire. If it isn't, work the tube back into the tire all the way around on both sides. Once you're satisfied the tube is fully inside the tire, reinflate. Also, ensure the tire is the right size for this rim.

  • The tire is the original for the bike. The inner tube is not, but it was replaced by a bike shop looking at an original inner tube. Could inner tube sizing be part of the problem? – cr0 Nov 8 '16 at 15:54
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I had a pair of stock tires that had the same issue. Unless I physically held the bead in place during inflation, there would be parts just like in the video, where the bead was getting sucked into the rim. It was ridable, but I could feel the dip every revolution. I couldn't find a solution by fiddling with inner tubes and rim tape, but replacing the tires with some higher quality ones totally solved the issue. If it's in your budget I would just replace the tires, better quality ones can make a big difference in ride quality, too.

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