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Road bike rim - 700c rim - rim ID 15mm - rim OD 22mm - rim bead 3mm - new Continental Gatorskin tires - Continental Race 28 700c tubes 20-622 > 25-630 -- 700 x 20c > 700 x 25c

  • 42 mm Presta stem.

I ride about six miles and I get a hole in the tube near the valve stem. I checked the rim and the tire for sharp spots or objects. The spokes are all tight. The bike rim tape looks OK, it is tight and smooth.

Any ideas why I keep getting holes in the tubes?

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  • If you had a Schrader valve I would suspect a sharp edge in the rim around the valve hole. But if you have metal Presta valves this is unlikely. Aug 13, 2022 at 22:11
  • Can you add a photo of the rim at the area where the puncture occurs? At this point I suspect the rim tape - they can look OK but be thin. Fortunately they're not expensive, and options like paper painter's tape can help beef up a thin rimtape. Photo, please?
    – Criggie
    Aug 13, 2022 at 23:57

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New tubes and tyres rules out the possibility of a sharp thing embedded in the rubber.

Look closely at the hole and figure out what side its on.

Hole location Likely causes Remedy
The same side as the valve Spoke/nipple poking through rim tape

Rim tape moved off spoke-hole
Remove tape and file point smooth

Slide rimtape back into place, or replace.
Outer rolling surface Sharp thing embedded in tyre Invert tyre and look in that quadrant.
Use a bright light and a pick
Small twin holes about 10mm apart Snake bite - riding at too low pressure Increase tyre's air pressure
Ragged flappy exploded look Hernia - tyre has a large hole/cut, tube pokes out Install boot inside the tyre, and buy a new tyre soon.
Within 10mm of valve Sharp edges in rim Deburr rim's valve hole
Single cut on "side" Pinched tube during installation Work on your technique
Seams in tube peel apart Perished rubber, old age, poor storage Replace tube

There is also a possibility of tube having a manufacturing defect too.

Aside - some technique here can help too. Always put the tyre on in the same place, with the logo at the valve stem, and correctly matching any rotation markers. This helps a lot with isolating the area causing the puncture, gives you less tyre to search.

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    Update: I bought five tubes, all the same, some time ago. I installed a new tube, again. This time I used a small paintbrush to powder the inside of the tire, the rim, and the tube, reassembled the wheel and inflated the tire to 100 psi. So far no flats. The problem may be the tube is one size too small for the tire. I'll update as more information is collected.
    – user66335
    Aug 17, 2022 at 11:53

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