Originally Posted by
whk1992
Last year, I got lots of flat tyres (once every month or so). Finally, I talked to a bike mechanics, and he suggested that I should fit a larger tube inside my tyre. Then, he fitted a 28c tube in my 23c tyre. I have never had flats since then
The fix is actually reasonable. The larger the tube is, the less stretched it will be. That is, the tube's wall is thicker.
It's actually more complicated than that. Not only is the tube thicker, but because it has to stretch less from its uninflated size to fill the tire casing, it's under less strain from that. That means that tube walls may well be under compression, and not tension, which means that they push into any hole, instead of pulling away from it. If there's a hole, you're going to get a flat, but that force can be enough to keep something from puncturing it. Michelin sell a tube that exploits the property, but also adds a sealant to the tube.