I got a used trainer and trainer tire off of Fb marketplace.

I installed the tire, pumped it to to the recommended 100 PSI and I noticed a bulge. I thought l had installed it incorrectly so I removed it and reinstalled again.

Here’s a picture of the worse case during my multiple attempts. bulging tire

I noticed that it was always around the valve.

Eventually, I was able to install it, but there was still a little bit of a bulge. At least the inner tube was not popping out.

My approach was basically to install the tire, pump it up a little bit, adjusted the tire to make sure that it’s sitting well. Pumped it up some more and repeated.

Is there a special way to install these trainer tires? Was I just doing it incorrectly? The fact that it was always around the valve seemed like it’s a clue that maybe I didn’t seat the tire correctly around the valve.

  • Silly question: Are you sure the tire is the right diameter? Commented Jun 14, 2020 at 13:11
  • 1
    Good question. I have a 700c wheel and this is correct tire
    – milesmeow
    Commented Jun 14, 2020 at 21:10
  • You're sure the tire's not a 700b? Commented Jun 14, 2020 at 21:27
  • 2
    But a hint, if the problem is always near the valve: The tube is thicker there, and often the tube gets caught under the tire beads as a result. One trick is to loosen the lock nut and push the valve through the rim about 1/2 inch before seating the bead on the rim. This helps prevent the tube from getting caught. Commented Jun 14, 2020 at 21:29
  • 1
    It’s a 700 x 25c tire.
    – milesmeow
    Commented Jun 14, 2020 at 21:30

2 Answers 2


Make sure you are fitting the tire correctly. Examine the bread all the way around the rim on both sides and make sure it is seated evenly.

I wonder if the inner tube is not properly inside the tire near the valve. The reinforced area around the valve can get stuck under the tire bead. Before inflating, push the valve into the rim to make sure the tube is properly inside the tire.

If you still have problems try marking the tire where it popped off the rim and mounting the it rotated 180 degrees around the rim. If it comes off the bead in the same place the issue may be damage to you rim that the loose fitting tire is revealing. If the same section of tire pops off the tire bead may be damaged at that point.

  • During my many attempts I turned the tire just to make sure that it wasn’t an anomaly with a certain part of the tire. The tire is okay, it was always around the valve. This valve stem also has a metal nut that will pull the stem tight against the rim. So I pumped up the tire a little bit and then righted that nut, and then adjusted the tires to make sure that it was seated ok.
    – milesmeow
    Commented Jun 14, 2020 at 21:05

Do you have the stem nut tight? I'd back that off a lot when fitting the tyre - at this point its main job is to stop you loosing the valve into the rim while working the tyre.

Also, I'd make a point of starting the tyre on the rim near the valve, and then work away from that spot. Valves can be a little fragile, and their mere presence makes it harder to get the tyre in place on the rim.

Try to get the tyre's sidewall label at the valve too, and check your rotation arrow direction before committing.

Another possibility is that the previous owner used this tyre on a tubeless rim, and the crochet hook / bead hook is somehow distorted, allowing the bead to unhook under pressure.

Your last resort is to throw the trainer tyre out and use up one of those "spares" that you have hanging in the shed. I certainly have a bunch too good to throw but not good enough to commute or race.

  • 1
    Thank you. I didn’t know there was a rotation direction! I don’t see a marking on my tire. Whew. After what I went through I wouldn’t want to try to put the tire in again. LOL
    – milesmeow
    Commented Jun 14, 2020 at 21:09

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