I was able to wear it for a while, but the bike turned out to not be an option, the stretcher was pulling just a bit too hard for that to be comfortable. I ended up having to take it off after a short while.
A word to the wise, don’t try to wear a stretcher if your ball sack isn’t fully relaxed, it just won’t be comfortable to put on, or to wear. Oh, and use lube to help put it on, even if the sack is fully relaxed, it helps prevent pinching by allowing the skin to slide around freely. (try to dry your hands before putting the stretcher on, so that you can keep hold of the metal.)