DrSafe draw length is , pull it until it beaks and back off a tad from there!
But seriously, you should know your draw length, or you target draw length, but what the bow can manage also depends on draw weight.
E.G.
If you push it to 60# then the draw length may be say 28" above which it will start taking set/exploding. But at 40# it will maybe take 30" before taking set/exploding.
It's always a compromise.
Del