Why Do my Inner Tubes Keep Puncturing on the Inside?

Expert advice from the people above eh?

It seems like you've checked everything but can I just run over a few things?

Interesting theory regarding the rim hole being too big, only you can judge that, 'cos I can't see it! Another possibility is that your tube is under-inflated and subject to rolling around on the rim, as you ride your bike and the tyre is under compression!

If you are using road tubes, then no doubt you have presta valves, just make sure you do up the little knurled nut on the valve stem!

Another idea to run by you, - is over exuberance with your pump, as you are inflating the tubes, - be carefull!

Give a quick rub with some sandpaper(or small file)around the rim hole and use any offcuts of rim tape to ensure it runs right up to the hole!!

Sounds like common sense but we all overlook simple things sometimes (even me!).

Best of luck.

EDIT:

Thanks for your additional details but I'm out of ideas, so I'm going to side with one of your suggestions "The unluckiest guy in the world" !!

Bike Inner Tube

Is it 1 or 2 punctures (snake bite)? 2 punctures may mean under inflation. Just exactly where is the puncture at? Is it on the inside diameter of the tube which would be next to the rim strip or is it on the outside diameter of the tube which could mean that there is something still in the tire that may be the cause?

I've had a couple friends run into the same problem. In both cases it was the rim that was causing a punture in the tube.

In both cases I ran my finger across the rim but couldn't find anything. Only after a detailed inspection by a bike shop did they find the protrusion.

Take it to a bike shop and see if they can find it. Or send it to the rim manufacturer and have them figure it out.

Good luck to you, I know it can be frustrating to be constantly changing tires.

The biggest cause of flats on road bikes is inadequate pressure. make sure you are inflating to the max pressure. Use a gauge, and remember gauges on cheap pumps usually aren't accurate.

make sure you are using tubes with the right valves. Next time you buy tubes look at tubes with both Schrader and presta valves and see if one fits the valve hole better. and if they come with a screw on stabilizer, make sure you use it.

make sure you change the tubes in a very clean environment. A few grains of sand inside can puncture your tube.

Do you have new tires? I once had a set of tires (Michelin Speediums) that gave me flat after flat, no matter what I did. When I changed them, the problem went away.

consider using tougher tubes, like maybe these:

http://www.performancebike.com/shop/profile.cfm?SK...

good luck to you. I have been there, and getting lots of flats is very annoying,

What are you using for a rim strip? Rubber or the plastic ones are out of the question - tire air pressure is too high for them, especially if it is a double wall rim. The high pressure forces the plastic one down into the spoke hole & causes it to split & cut tubes. The splits aren't always noticeable, but you will see where the plastic has stretched down into the spoke hole. The rubber ones can push in, exposing the edges of the holes. Use Velox or another adhesive-backed cloth tape. They hold up better and won't split like plastic or dry rot like rubber.

Don't pump it up without it being in the tire the tube stretches too much. Make sure you rough up the tube so the glue has something to hold on to. Also let the glue haze up and get sticky before you put the patch on. Don't reuse the patch and you can't patch the edge of a patch. Also check the tire for the cause.

Probably if you use presta valves and you are intalling the nut that come with the tube the preassure might be smaping the valve from the tube. If not you are actually the unluckiest guy in your state because the same thing happended to me.

I'm guessing #4 and somehow there's a tiny abrasion you're missing ... take a couple wraps of duct tape all around the inside of your rim, poke a hole big enoug to force the valve stem through, should cure it ...if it doesn't your suspicions are right,

I think this question belongs in "things that go bump in the night". The only thing I can even guess is the tubes are getting kinked as they're installed.