Hi there,


I made a nasty split in my inner tube. I have been trying to patch it, without success.

The way the split was made is the following. I rode on a nail. It pierced the inner tube from the outside, but the problem is that I walked my bike home without removing it, because I thought I had a flat tire for another reason.

The nail thus made a very small hole on the outside of the inner tube, but two large rifts on the inside.

I have tried patching both sides by making patches from an old inner tube.

The small hole on the outside got patched perfectly, but I couldn't get the inside large rifts to heal at all.

Here's what I did:

• I rubbed the area around it well with sandpaper
• I cut a patch in the old inner tube, trying to make beveled edges with a box cutter
• I sanded the patch well, and sanded particularly well the edges, to try to make them thinner
• I cleaned both surfaces
• I applied rubber cement from a Zefal kit on both surfaces
• I let it dry for 5 minutes, as indicated on the Zefal kit's manual
• I applied the patch, pushed well on it with the tire removal tool
• I stepped on it for 2 minutes
• I reseated the inner tube, pumped it lightly so that it would press against the tire edges
• I waited till next morning

In some cases, the inner tube would still be inflated on the next day. I would then pump it to 3 bars, but then it would deflate within less than half an hour, without using the bike.

Alternatively, I also tried pumping directly to 3 bars right after stepping on the applied patch, but it wouldn't hold at all.

Sometimes, after deflating, I would take the inner tube out, submerge it in water, pump it a little, and it wouldn't leak at all. Surprisingly, I would have to reseat it and pump it to 3 bars for it to deflate again.

I tried some variants, for example smoothing the glue layer with my finger before letting it dry, no change. I also tried letting it dry for 15 minutes, no change. I also initially tried to just cut the patch without beveling the edges, no change.

I've been failing for about 10 times in a row now.

Each time it's pretty easy to peel the patch off, most of the time it even remains in one piece.

Could it be because I am making these patches myself? Would the result be any different with a bought patch?

Could it be because there might be remains of glue from my first and subsequent attempts, that prevent the patch from adhering well?

Any idea what I might be doing wrong, or how to fix my inner tube?

I am trying to upload pictures but the forum won't let me, you can check them out at drive <dot> google <dot> com/drive/folders/1ZUAiv8zLEL8nRBpdpWs4Qkd-F_1HX3YD.

Thanks a lot in advance for the help!