RandomTroll

Most of my flats I can associate with holes in the bottom of the tube and thorns, bits of metal or glass, etc., embedded in the tire or liner.

Sometimes I find small holes in the side of a tube, 90 degrees from the bottom, usually right on the ridge that runs along the side of the tube. I never find something that would have punctured the tube in the tire, or sign of penetration of the tire. They're past the part of the tire a liner would protect. Sometimes this happens repeatedly, every day or 2 or 3, on a different place, on the same tube, often when the tube on the other wheel has no problem (i.e., I don't encounter lots of thorns.)

I assume the ridges that run along the tube are artifacts of manufacture, not seams, but I don't know how they're made; maybe they can be flimsier. I've also wondered if they aren't, perhaps, at the edge of the liner and a defect in the liner does the dirty work. I inspect the liner for flaws in its edge; if I find one I discard it. Perhaps they merely rub the tube the wrong way occasionally.

dabac

Tubes do indeed have seams from manufacturing. But AFAIK they are crosswise, not lengthwise.
But quality control and wall thickness isn't 100%. I've had the occasional tube develop a lumpy appearence, associated with spots of noticeably thinner rubber. A little bit further down that road, and seemingly mysterious flats would have been the result.

Looigi

No seams in the tubes I have. They are molded in one piece. There a lines in them which are parting lines for the mold segments. Cut a tube open and you'll see there are no internal lines or seams.

Small longitudinal cuts on the sides of the tubes can be due to pinch flats, where the tire is compressed by a sharp edge in the pavement or an object far enough that the tube gets trapped and pinched. Depending on the conditions where you ride, how you ride, and the tire pressure, these can be relatively common.

stevnim

Thank you for asking this question! I had never thought about tube manufacture before, went looking on YouTube and found this. It's not the best quality video, but you get the general idea. https://www.youtube.com/watch?v=X4cQ-R6ysmw

speedy25

They broke the cardinal rule when working on a rubber mill- You dont talk to others and they stay away from your work! You dont want fingers mixed in with the batch. (I have done this work before.)

Anyway, OP- I think your real problem is not enough pressure in your tubes. You didnt say what it was you were getting holes in so we cant make recommendations.

-SP

fietsbob

the Mold they are made in has to come apart to let the product come out ..

the edges of the production mold sections, produces the lines you perceive as seams ..

Not occasionally, Tire liners move inside the tire with every rotation , that hole is a result of that internal abrasion..

I have stopped using them , but in the Shop I grind off the end on a bench grinder to taper the cut end.

I suggest you use an abundance of Talc in the tire .. and renew it occasionally

Thorn resistant tube are a lot thicker on the edge towards the street ..

RandomTroll

You're welcome. I inflate my tubes to 100 psi every day. I occasionally catch the edge of a rock when off-road and pavement, but not as often as these events can happen when I have a rash of them. I inflate my tubes to 100 psi every day. Huh? I'm getting holes in my tube. Then why doesn't it happen all the time? I rode from Los Angeles to eastern Oregon in 1989 without a flat the whole time until I wore out the rear tire and the tube expanded through it. I used liners. It doesn't happen at the ends. The last time I shopped for talc I couldn't find it anywhere. I settled for baby powder which was talc with perfume. Those baby products are all scams: NONE of them are made from real babies! I figured they would press them for oil then grind up the bagasse for powder...

fietsbob

consider your self lucky .. :|


Now I Buy Schwalbe Marathon Plus Tires ..

Rema, the Tube Patch company makes industrial Talc in a Shaker Can..

Andrew R Stewart 

I have used flour as a desperate sub for talc. Andy.

rm -rf

The cut is probably from a pinch flat. But last year, I did have a tube (Michelin lightweight butyl) split a quarter inch long, exactly along a seam line, and I hadn't hit anything on that ride.