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The rim tape on the rear wheel has blown out a couple of times in the same spot. Luckily, while parked. Is there an issue with the rim that needs to be fixed? What can be done to avoid the problem from reoccurring?

The wheel is a Giant SR2. Always run at 100psi, the recommended PSI range is 85-115. The first time it blew it was tubeless. After that it has been run with inner tubes.

The only puncture of the inner tube is at the spoke hole that has lost its rim tape. enter image description here enter image description here enter image description here enter image description here enter image description here

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    Is the length of brown some kind of stick-on tape? Can you feel any sharp edges around that spoke hole? I can't see any of what I'd call "rim tape" in your picture.
    – Criggie ♦
    Apr 17, 2021 at 23:26
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    @Criggie The brown length is tubeless tape, LBS who sold the bike gave it to me after the first blowout along with instructions to apply, and said it would run fine with either inner tubes or sealant. I can't feel anything sharp through the tape.
    – Scottmeup
    Apr 17, 2021 at 23:34
  • How many layers of tape are you using? Try deburring that hole as suggested.
    – MaplePanda
    Apr 18, 2021 at 2:53
  • The rim tape looks awfully thin. Get some proper tape from e.g. Schwalbe or Continental.
    – Michael
    Apr 18, 2021 at 10:04
  • Also, your tape is a bit too narrow. You want it going from rim wall to rim wall without any gap.
    – MaplePanda
    Apr 18, 2021 at 18:17

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I would suspect that your rim tape isn't up to the job of spanning those nipple holes against the pressure of your tubes. Tubeless's big selling point is lower pressure, but your tube is double that pressure.

Additionally, those holes do look quite large - visually they are almost out to the ledges. It may be worth searching the web to see if this brand/model of rim is known for puncturing here. It might be a model that uses plugs over the nipple holes, but they haven't been fitted.

After you peel off the old tape, I'd suggest deburring the holes with a fine needle file or deburring tool or similar, for peace of mind if nothing more. It doesn't take much effort.

My personal preference would be for the rim tape that comes as a loop, not in a roll. Most of the major tube manufacturers make rim tape, and it should be sized for your rim diameter and width. This stuff is stretched over the rim and will shrink back down to a tight fit, so it can't slide around the rim. You can stack rim tape to a point as well, as long as it doesn't interfere with the tyre bead.

Example (not a product rec):
enter image description here

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  • Just wondering if you might know what pressures would be safe or expected based on it having tubeless tape? When I contacted LBS and Giant they both quoted the specifications on the tyre for running either tubeless or tube. I've always run it at the centre of the upper and lower pressure limits.
    – Scottmeup
    Apr 18, 2021 at 2:26
  • @Scottmeup I'm not qualified to answer cos I only use tubes, but pressure is a factor of your weight. I'm 95kg and the bike is 12 so at 110 kg total I use 90 PSI in 28mm tyres. That's on the high side for most people. For tubeless road, my impression is you can knock 10-20% off the pressure for the same width of tyre, but that's a dingy memory. Tubeless offroad is another matter altogether with far lower pressures than seems possible.
    – Criggie ♦
    Apr 18, 2021 at 4:21
  • @Scottmeup If this problem isn't resolved by better rim tape and deburring, you might need to consider something like a set of veloplug.com which block each nipple hole underneath the tape. (not a product rec, just the idea)
    – Criggie ♦
    Apr 18, 2021 at 4:22
  • For running tubes at high-pressure put a loop type rim tape over the tubeless tape as Criggie suggested. When running tubeless simply remove it. The whole point of tubeless is running way lower pressures without risking pinch flats. So get those pressures down.
    – gschenk
    Apr 18, 2021 at 13:08

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