Can't say how long ago the tires were manufactured, but I bought them about 3 years ago and the bike store's only existed for 4 years. Don't know whether the bare cotton outer layers are relevant or not since the base tape still has to be attached to the tire by the manufacturer with some sort of adhesive. Looks like the adhesive I used on those tires is red rather than my usual clear. I'm certain some adhesives other than Continental will work without problems. The question is which are okay, and which not?