I noticed that none of us has mentioned that the surface of the tube needs to be cleaned of any lubricants or silicone products. Often soap, tire foam, or butyl rubber preservative is on the surface of the tube.
What ever you use to clean the tube it should not have any lubricant left over after evaporation. I have used Simple Green with water, Denatured alcohol, Acohol pads, Gasoline and others.
If on the road I will put a thin layer of vulcanizing cement in the area of the patch then wipe it off using the cement as its own cleaner. I then apply the patch normally.
Further note that I put vulcanizing cement on both the tube and the patch. Many of my patches are pretty much died out and need to be revitalized by the cement.
It might seem like a waste of cement that I carry in my little kit but I consider the little tubes one ride use cause when once opened they are usually done for.
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