Originally Posted by
soyabean
There is absolutely no reason why a folded tyre can't be installed immediately from new stock.
I've never heard of letting it "air out" in advance.
The key phrase might be "from new stock", because the longer it's been folded the more likely it is to be annoying, I think. Not difficult, just annoying when it won't go on the rim because it's both too floppy and too kinked.