I will try to keep it to the point. Note this is not my first time pulling a motor, but I know mistakes were made somewhere . I want some input so it doesn't happen when I pull the second motor. 2013 ZX6R on front headlift and rear stand. Wheels still on, suspension still on. Jack placed under motor. Main engine bolts loosened. (Maybe needed to loosen the lower engine bold more. Removed top and middle engine bolts. Jack still under motor. Went to remove lower engine bolt and found it to be tight. Tried to take some pressure off of it, still tight. Thought maybe it was just put on too tight last time. Turned it, and snap. Cracked the bottom of the frame. Where did I make my mistake?