My case is the cooler master masterbox lite 5. 3 fans in front and one fan for exhaustIf I am not mistaken, 85c. is the throttle point for ryzen.
The chip should throttle or shut down to prevent damage if it senses a dangerous temperature.
From that point of view, it is safe.
From a functional point of view you want to run cooler.
What is your case and fan arrangement?
The stock cooler should do the job if it gets sufficient cooling air.