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Discussion Starter · #1 ·
I'm trying to figure out why I keep puncturing tubes. I just bought a new bike, haven't ridden it even 100 miles. On my way into work yesterday, I had a sudden loss of pressure. All of my issues have occured on smooth flat road, and I didn't hit anything. The tire was flat within a few seconds I was probably around 95 psi on a tire rated at 100. I patched it and rode on in. On my way home, it happened again, since I had pumped it using my frame pump this time, it was probably around 80 psi. This puncture looked the same as the previous one. I installed a new tube, and this time, using a floor pump. At around 95 psi, the tire ruptured in the same way, it wasn't even on the bike or under any weight. Thinking I had pinched it while installing, I patched it and this time only inflated it to 80 psi. It ruptured again. All of these failures have occured at different parts of the tube. I've ran my fingers along the inside and outside of the wheel and tire.

I'm going to take it in to the shop where I bought it after work, but maybe someone here can give me an idea of what I'm doing wrong. Here are pictures of one of the punctures from a few different angles.

https://keithkris.com/tube1.JPG
https://keithkris.com/tube2.JPG
https://keithkris.com/tube3.JPG
 

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Discussion Starter · #3 ·
Dave Hickey said:
Is the hole on the inside or outside of the tube? It might be bad rim tape causing the problem..... Velox is cheap and it's the best...
It looks to me like it's on the side of the tube, and it's happened on both the left an right side (unless I'm installing the tube in different directions each time, I've only just learned that you should be attentive to that.)
 

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I just went through the same thing a few weeks ago when I first got my bike. You are in the pinch flat learning curve. Get yourself to youtube.com and search out little videos on road bike tube changes. I can tell you that pry bars are an absolute evil when you're installing the tube. You can use them to remove the tube but they will chew a hole in your tube installing.
So, to install:
-Take the tire and put one side into the rim-rotate the tire on the rim to have some easily remembered part of the label lined up with the valvestem hole(for finding out where flats occur in the future).
-Blow a little air into the tube to give it some form but no stiffness.
-Stuff the tube as far up into the tire as you can. and insert the valve stem. Don't put the little silver stem nut on yet!
-By hand only, wiggle, cuss and thumb push the 2nd side of the tire into the rim. I like to save the valve stem area for last, so I start opposite and work both sides kind of alternating a few inches on one side then the other until I reach the stem from both sides.
-Be paranoid about the stem area. It seems the hardest area to seat correctly. Shoving the stem up firmly but not too crazy helps.
-After you think you've seated the rim into the tube and it all appears evenly sunk into the rim walls, grab the tire one handwith at a time and wiggle it firmly back and forth. Try to "feel" getting the tube to wiggle up into the outermost open area inside the tire. Go around the whole tire once or even twice doing this.
-Shove the valve stem up one more time firmly to insure it seated properly. Put the silver washer on-not too tight! (You can actually rip the presta valve to rubber transition area!)
-You're ready to inflate. Be careful about manhandling the pump fitting on that Presta tube valve. The're pretty fragile.
Hope that fixes it for you as it did for me.
 

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Whenever I get a flat I try to install the tube in the same position as it was. I like to line up the valve stem and the label on the tire. That way if I do get another flat, it's easier to look for the cause. Something that hasn't been mentioned is the possibility of a too long spoke. You might want to ck for this. I also agree about not using tire levers to install. I haven't been able to do this without pinching a tube in the last 200,000 miles.
 

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still shedding season
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Check the inside of the tire carefully, and if you have the writing on it lined up with the stem you'll know exactly where to look (well, one of two places depending on rotation). Also check the inside of the rim. I had a tiny burr that showed up somehow, right on the seam of the wheel. Maybe I hit something just right in that spot, don't know. It was about the size of a grain of sand so at first I didn't think it was a problem (I'm new at this too). Second popped tube in the same spot told me differently so I filed it smooth and it's been fine since.
 

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scruffy nerf herder
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question...... wire bead or folding? Ive seen wire beads poke through, especially when someone tries to turn it into a folding...

And two.. on the side... could there be an install issue? Try putting a little air into the tube first. It will make it less apt to roll under the bead when reseating it.

Lastly... check all the spokes. If this keeps happening... good chance you may have a spoke coming through. this goes back to rim tape though.
 

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I got 3 flats in the first 150 miles or 500 miles when I first got my bike with the $12 stock tires. Then I didn't get any more flats for the next 7,500 miles with those tires. Go figure. The less tread, the less flats? Doesn't make sense.
 
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