Originally Posted by
SortaGrey
Don't bother. Set that rear in there.. spread with your fingers and insert. 'Cold setting' is just slang for 'could f it up'.
The issue with that is that the dropouts won't be parallel, which isn't particularly good for the bearings in any hub, and is a very bad thing with any kind of internally-geared hub. Properly cold-setting a frame involves aligning the dropouts afterwards.
It all depends on the distances involved, a 130mm OLD hub in a 127mm frame isn't going to be a problem even if you don't cold-set, but things get iffy going for bigger differences than that.