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Well, I am new to road biking and I got my first flat yesterday. I was going to go for a ride and the front tire was completely flat, so I popped it off and went to patch it. I found the hole, it was on the rim-side, and I noticed that the rim tape had slipped off a little and the spoke hole was slightly exposed, so I pushed the tape back to position, patched the hole, and pumped the tire back up.

As I was pumping it up the patch blew out. So I went back and tried to stick another patch on, and it blew out too. I ended up going through about six patches before I got one that 'worked.' I let it sit a couple hours and it was holding pressure just fine. After about 4 hours I was going to go for a bike ride and it was completely flat again.

I took the tube off again and there was a wrinkle that formed in the patch where the air is coming out. I checked the rim tape and it was fine, none of the spoke hole where sticking out. My current theory is that the tube is conforming to the shape of the rim on the inside, right where the patch is, and forcing the patch to wrinkle and inevitably blow out.

I am completely at a loss as to what to do here. I've patched tires on my mountain bikes many times and have never had this much trouble. I don't want to get a new tube, I have only like 60 miles on this tube. Should I just try slapping another patch over this patch's wrinkle and hope for the best or should I just start from scratch with a new tube and rim tape?

Thanks.

  • When you took the tire off the second, third.....sixth times, was the rim tape positioned correctly? – BSO rider Oct 2 '15 at 23:54
  • @BSOrider The rim tape did seem to be positioned correctly, and after the second or third try I flipped the tape the other way around so that it would not fall back into its old position, and after the tries after flipping it, it was positioned correctly. – reconrey Oct 3 '15 at 0:02
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    I think you have some bum patches, or you don't know how to install them. Also, you may have an overlength spoke that pokes through the spoke hole at intervals -- check spokes in the area to be sure they are all tight. – Daniel R Hicks Oct 3 '15 at 0:38
  • I don't think over length spokes is an issue, they are all recessed quite a bit because of the rim design. Also, I tried two different patch kits, one was made by Slime (first ones I tried), and the last one I tried that held for the longest was a Park Tool patch kit. And to install (after having issues with the first two), I tried using the method on the package and the guide on Sheldon Brown's site. – reconrey Oct 3 '15 at 0:51
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    As Chris H says, never (except in an emergency) attempt to patch a tube on the road -- just swap in your spare (you should always have one), and fix the failing tube when you get home. (You still need to find the leak, though, to assure that there's nothing that will puncture the replacement.) Using glue-on patches I have never, to my recollection, had one fail, except when directly atop a "seam" in the tube. – Daniel R Hicks Oct 3 '15 at 12:02
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I'm not sure why this question needed four paragraphs to explain, but I'll indulge it. However, I want to point out that the most effective decision is whatever results in a reliable tube using the least amount of time, money, and effort to accomplish. That should be obvious and not need to be pointed out.

That said, I would personally buy a new tube and rim tape. I might even buy a new tire while I'm at it. If a tube keeps going flat, there are only two or three possible explanations.

  1. The patch isn't taking
  2. The rim or something in the tire (e.g. small, short piece of metal) keeps puncturing the tube
  3. The tire is worn through/weak in a specific area

There is a certain level of convenience in patching a tube. If you're having to patch the same spot on a tube multiple times or keep getting multiple flats on the same tube in a day, or even a week, is it really worth your time to diagnose when you can spend ~$5 on a new tube and rule possibility out (unless you're extremely unlucky and get a defective tube, which has happened to me once)?

If you feel it is really worth your time, you can rule out the first potential cause by pumping up the patched tube outside of the tire, and putting it in a tub full of water. Watch for air bubbles.

You can try ruling out the second by running your finger through the rim and through the inside of the tire, but BE CAREFUL! You can slice your finger open if there's something sharp and big enough poking through.

The latter is something you can only determine through visual inspection. I know one of the most confounding flats I've ever had was caused by a small cut in the tire, big enough for the inflated tube to poke out of, embolize, and eventually blow out.

  • The issue seems to be with a wrinkle forming after I re-seat the tire in the tube. It holds air fine until I put it in the tire and put some pressure in it. – reconrey Oct 3 '15 at 16:09
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    "Seems to be" is another way of saying "I have no idea and am making an assumption". If this "wrinkle" is actually the cause of this, it's happening because the patch hasn't completely adhered to the tube and by re-seating it in the tire, it's been shifted. The fact that it's holding air prior to re-seating doesn't mean it has adhered completely. – Chris Olin Oct 3 '15 at 17:18
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    Welcome to SE Bicycles, that's an excellent answer. – Criggie Oct 3 '15 at 20:17
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While I dont like the throw away and not repair philosophy these days, I would say that 6 patches are more expensive than a new tube. Mine, at 1.50 euro the piece, are not best quality but have been enough for thousands of kilometers. As for patching, I believe that if you patch properly no spoke should move the patch. In any case,the hole should not be unpatchable unless very big. And what about flipping the tube to avoid contact of the spoke and patch, or is it just in the opposite side of the valve? Lastly, I 've found that when patching, leaving the paste solution to dry for some 20 seconds longer than the typical recommended minute helps the patch stick and not move.

  • The issue is not with it rubbing on the spoke, at least I don't think it is. I cannot really see any way to move the tube so that the patch would not be in the way. I think I may try throwing one last patch over this patch's leak and hope for the best. Otherwise I will just buy a new tube. – reconrey Oct 3 '15 at 2:39
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I always swap out the tube and do my patching at home when I'm out of spare tubes (stock up if you see them on offer). This is partly to stop the glue going off in the tube, but it means that when I do patch it's easy to do it perfectly and not rush.

My recipe: The tube is dry and slightly roughened, plenty of glue, let it go tacky (if I'm rushing I can never get a patch to take), then patch. Just enough air to get the tube to take shape and a bit more glue smeared round the edge. Then leave the tube while you do something else. It will need some chalk when you come back to it.

I've never got on with glueless patches though some people here love them. It always seems impossible to get the backing off in one go, unless it's falling off when the patch doesn't stick to the tube.

The only time I've had trouble with wrinkles forming is if I've patched over the seam in the tube. Extra glue helps then,but it takes ages with no pressure to dry.

  • Another thing: When I'm applying a patch, after the patch is in place and has "set" a few seconds, I take the edge of a plastic "spoon" and rub the patch back and forth repeatedly, pressing it tightly so that the glue bonds well. – Daniel R Hicks Oct 3 '15 at 12:04
  • The hole is right by a seam and the patch is covering the seam. However, I sanded down the seam when roughing the surface, so I'm not sure if it would make much of a difference. – reconrey Oct 3 '15 at 16:06
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I had this happen one time on a stint down the coast. Six flats. All rim-side. Lovely. I've already seen some good solutions above, but I'll throw in my two-cents just for clarity's sake.

First, it's probably not the patch but the tube getting re-punctured/stressed in the same place - the patch just happens to be there, so I would (as someone above suggested) switch out rim-tape (that being said, try using a new tire just to take that variable out of play). Also, run your finger inside the rim to see if there are any sharp pieces sticking out either on the side or from the spoke hole. You may need to use a file to smooth them out or remove them. You didn't describe the puncture, and it may have been caused by the spoke-hole, or it could have been something else. It's worth taking a closer look - if it's a length-wise cut, rather than a puncture, the rims are biting into the tire, and the rim-strip should fix the problem - as long as it's wide enough. Also, when you see the rim tape sliding around, you have to ask 'why?'. You may have been riding on underinflated tires, or had a small collision with a curb which created the stress that caused the flat.

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