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Resident Curmudgeon
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Discussion Starter · #1 ·
Just last week I put new Gatorskins along with brand new Michelin tubes on one of my bikes. Went for a ride, everything was perfect. I came out the next morning to find a flat on the rear. I was late for a ride & I didn't have time to fuss with it so I put another brand new Michelin tube in.

During the ride everything was fine, put the bike away & came out the next morning to find the rear flat.

OK, this was getting tiring. I pumped up the flat tubes so they were as big around as a softball. I put them in a bucket & very carefully checked for bubbles. I looked with the valve screwed in, and again with the screw out. Nothing! Not 1 single bubble & I looked very closely.

I went to my workshop & installed a different, new, never ridden Gatorskin & a brand new Michelin tube. I've been on several rides since then & the tire has stayed perfectly inflated...no problems at all.

Why did the other tire & tubes go flat? They were both brand new & I could find no fault either with the tire or the tubes.
 

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Big is relative
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I've gotten small pieces of wire from a shredded steel belted truck tire in my tire. If you run your hand inside the tire looking for a flat cause and you only check in one direction, the small piece of wire can just lay down. You have to check in both directions. It'll give an overnight flat or may just cause a more than normal pressure drop day to day. The hole in the tube is very tiny, I'd inflate and have to squeeze the tube when submerged to ever get a bubble. For me, it's always been the rear tire.
 

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for a hard to find leak try putting a few drops of dishwashing liquid on a paper towel, wet it and rub it on the inflated tube. After a short while even the smallest pin hole will get some foam building on it.
 
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I've gotten small pieces of wire from a shredded steel belted truck tire in my tire. If you run your hand inside the tire looking for a flat cause and you only check in one direction, the small piece of wire can just lay down. You have to check in both directions. It'll give an overnight flat or may just cause a more than normal pressure drop day to day. The hole in the tube is very tiny, I'd inflate and have to squeeze the tube when submerged to ever get a bubble. For me, it's always been the rear tire.
Good point about the wire as it happened to me also and failure to find it cost me a second flat and a mediocre time on my first century. It may also be a leaking valve havefun
 

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'brifter' is f'ing stupid
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Just throwing this out there...any chance you inflated them the first time with CO2?
 

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Resident Curmudgeon
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Discussion Starter · #7 ·
No. I use CO2 on the road if I get a flat but always replace it with good ol' air when I get home.
 

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Resident Curmudgeon
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Discussion Starter · #8 ·
I'll try squeezing & see what happens. Thanks for the tip.
 

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Resident Curmudgeon
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Discussion Starter · #9 ·
I checked the valves very carefully, once with the screw all the way in & once with the screw out.
 

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These are all good possible causes but bigbill I think is on to something. This happened to me where I went through 4 tubes tire would go flat over night but would last for the ride. I found a very small piece of metal, size of a needle, embedded in the tire. No hole access on the outside because it was so small but when I turned the tire inside out I say the piece of metal. When this happens you must be patient and look over every inch of tire to find culprit especially the inside of tire. Advise do not run your fingers on the inside of tire trying to feel for objects your asking for cuts, been there done that. My rule of thumb is when I flat on road I check inside of tire to make sure nothing is still stuck in trend. Numerous times I have flatted put in new tube and when flat 2 miles down the road only to have to walk home because I only carry one spare tube and no patches when I ride. I changed this now I ride with one tube and 2 patches. If you have the tire check inside of tire by going over every inch while flexing tire you will find something.
 

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My last two were leaky valves (where they attach to the tube)on Michelin tubes. I had to wiggle them submerged in water to get them to slowly release bubbles
 

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OK, this was getting tiring. I pumped up the flat tubes so they were as big around as a softball. I put them in a bucket & very carefully checked for bubbles. I looked with the valve screwed in, and again with the screw out. Nothing! Not 1 single bubble & I looked very closely.

I went to my workshop & installed a different, new, never ridden Gatorskin & a brand new Michelin tube. I've been on several rides since then & the tire has stayed perfectly inflated...no problems at all.

Why did the other tire & tubes go flat? They were both brand new & I could find no fault either with the tire or the tubes.
Mount the tire and tube again and ride it. If it is flat in the morning, pump it back up and put the whole tire into a water pan (going around the wheel as you dunk it in the pan). You should be able to see tiny bubbles forming on the outside of the tire where the leak is. Sometimes it is darn hard to find very small holes but pumped to 100 psi you'll find it.
 

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I've gotten small pieces of wire from a shredded steel belted truck tire in my tire. If you run your hand inside the tire looking for a flat cause and you only check in one direction, the small piece of wire can just lay down. You have to check in both directions. It'll give an overnight flat or may just cause a more than normal pressure drop day to day. The hole in the tube is very tiny, I'd inflate and have to squeeze the tube when submerged to ever get a bubble. For me, it's always been the rear tire.
This. When I get a flat, I always take the tire off the rim and check the inside of it with two senses - sight and feel. I can't tell you how many club rides I've been on where a rider gets a flat and does a quick tube change without checking the tire. It usually has predictable results about a mile later.
 

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I had a slower leak than yours - I was pumping the tire every three days. Immersing the tube showed no trail of bubbles so I tolerated pumping for a couple weeks, then decided I was not going to be defeated. Instead of looking for a trail I looked for individual bubbles and found the leak.
 
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