Tires keep blowing
 

Hello. I have a road bicycle with vuelta airline 2 700c wheels in good condition. I have both a bontager black label and an armadillo tire. I keeping putting in bontager tubes from the local dealer, and they randomly blow when I am not riding. All of the punctures are on the inside diameter of the tube over spoke recesses. The spokes are tight, and no where near where the tube is. I have a double wrap of rim tape on both rims. I have tried psi from 80 to 115. I ride on roads and cement bike path. I am 250 lbs. Never get a flat when riding, always while bike is sitting in garage 2 or 3 days after I ride it. I have had this happen with 11 tubes in the last 3 months. Both front and rear wheels evenly. The last tube that went had 4 miles of smooth cement, and was at 110 psi. It blew 2 days after I finished riding. The local bike shop has no idea what is causing this. I have tried two different brands of rim tape.

I would greatly appreciate any help with this issue. I like to ride this bike for commuting, and am always unhappy when i find it has a flat tire before work.

My guess is that you have a small piece of wire or staple in the tire that finds its way through the tube. Remove the tire and check it very closely, inverting if you have to.

Ir is on the inside of the tube, opposite tire. And happens on both wheels

Try a different brand of tube.

I am similar in size .... it is possible that when you hit hard bumps the ends of the spokes stick far enough into the rim tape to stress the tubes. That is a lot of force to drop on a tiny metal stick ..... only alternatives would be something stuck in the rim tape (tire wires can get anywhere and hide really well) or ... you are pinching the tubes with a tire lever when installing them ...

or something else entirely.

From your description it seems as though the tube is not "blowing" rather it is forming a leak at an area where the tube passes over the location where a spoke is located in the rim. Since the rims on that wheelset are box section rims, the rim tape sags slightly at that location.
Assuming you are using a tube that is not undersized for the tire size, if the leak is more of a slit rather than a hole, try two things.
1. talc the entire tube. This acts as a lubricant and allows the tube to move during expansion and contraction instead of binding on the rim tape and tearing.
2. grease the inside of the tube. This has the same effect as talc.

Another option is to try a tube one size up from the tire size. 700x25mm tire, use a 700x28mm tube. Note that some tubes cover a wide range of sizes, if the tire is at the upper limit of size, go to the next size range.
One more option as pointed out in a previous post, use a different brand of tube that has thicker walls.

Don't forget to pull the tire off and inspect it closely paying attention to the tire bead. Even expensive tire manufactures have lapses in quality control. You could have a defective bead on the tire like a weak area of thickness. I have gotten to the point of using a caliper to measure the thickness and weakness of the beads on a new tire. If the bead rolls during a turn you can get a blowout or a pinch flat.

I have had two blowouts after riding, both with Vittoria latex "28-28" that seemed too big, like literally for a slightly larger diameter wheel size, that bunched up a little when installing. Both blew suddenly while not even moving, after rides. One was really stuck to the inside of the tire, like it needed talc but didn't get it. Replacements have been Kenda butyl tubes, which seem quite reliable in comparison.

It does tend to have a a slit where it pops.
Where do you get talc? Baby powder is all corn starch now.

All the tubes have the slit? My experience tells me to replace with a different brand of tube that has thicker walls. What I believe is happening, and I may be way off, but have seen this hundreds of times with thin walled tubes, at spoke hole opening where the rim tape sags (yes, even velox sags) the tube binds on the edges of the sag and stretches the tube into the sag and splits it open because the tube is being stretched too thin. When our shop started bringing in Qtubes from Quality Bicycle Products, a bicycle parts distributor, we stopped seeing this issue. The Qtubes had thicker walls than the Specialized tubes and when the tube was talc'd the problem abated.
Where to get real talc? Not sure where in your area. We have Meijer stores around here and they have it available. It is possible corn starch will work, but have never tried it.

Looking at images of those rims, man - those are some pretty big spoke holes in the rim bed, 'specially relative to the width of the rim; I could see how sag/expanding in to those holes might be a problem.

What kind of tape are you using? I'd be inclined to try:
- additional wraps
- a different tape
- rim plugs instead of tape

pic assist:
https://cimg7.ibsrv.net/gimg/bikefor...0a5a4fac35.jpg

Lose the rim strips and get some correctly sized Velox tape.

What type of tape are you using as rim tape? Could you provide photos of the failure points? Are there any patterns showing up elsewhere on the tubes from the failure points after they've been installed for a while?

I have some of this rim tape over a rim strip that claims to be for road bike pressures

I have some of this rim tape over a rim strip that claims to be for road bike pressures

You have got to be kidding me! It is not just the oil in the grease, but he additive package as well. You may have gotten away with this, but I wouldn't touch this idea with a 100 foot pole.

Also, what is the tire made of? And when the grease migrates onto the tire what will it do?

https://rubber-group.com/wp-content/...patibility.pdf

A blowout such as this is usually the result of damaging the tube when mounting the tire. Carefully following the best practices approach will minimize this problem greatly. I also avoid using tire levers as much as possible minimize damage to the tube. Most of my life I have used tubular or sewup tires so I needed to learn how to mount clincher tires on clincher rims without damaging the tube.

I am going to guess it’s from the way you mount the tire or use the tire lever

OP either lives in a home with a ghost that doesn't like bicycles or this. This could be a situation where the tube is inadvertently pinched against the tire bead during installation leading to failure.

My technique for installing tubes is

1-check tire and rim for sharp edges
2-install tube without tools
3-inflate to 10-15 psi
4-massage the tire around the entire perimeter to ensure that the tube is not pinched anywhere
5-deflate
6-inflate to desired PSI

This is a good puzzle! Hope the OP figures it out.

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What are you using as rim strip and tape? Why are you using tape over a rim strip? This sounds very weird, and the sort of thing that might create mounting issues.

Putting a tiny bit of air in the tube before installing (just so that it starts to take on a donut shape) is a good way to help prevent pinches. But I think problems with the rim tape should be investigated.

You're pinching the tube during the install. Are you using the right sized tube for the tire? Eg, are you using tubes meant for 25-28mm tires with a 23mm tire?

OP either lives in a home with a ghost that doesn't like bicycles or this. This could be a situation where the tube is inadvertently pinched against the tire bead during installation leading to failure.

My technique for installing tubes is

1-check tire and rim for sharp edges
2-install tube without tools
3-inflate to 10-15 psi
4-massage the tire around the entire perimeter to ensure that the tube is not pinched anywhere
5-deflate
6-inflate to desired PSI

This is a good puzzle! Hope the OP figures it out.

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