You can't even roll a Mig 21 faster than 180 degrees per second without the aircraft departing from controlled flight.
BTW, don't depend too much on your radar system in the Mig -21.
The Russians used grain alcohol for cooling the radar system and for the de ice systems and the Soviet ground crews used to steal the alcohol to get drunk with and cut the fluid with water to keep from getting caught.
The Soviets reported lost quite a few aircraft this way in Siberia.
More, in fact, than they ever lost in combat.
With any luck, our adversaries read your post and stock up Mig 21 to counter the F-35 threat.
F-35 pilots everywhere will offer a toast to your name nightly in officer's clubs around the world
Thank you for your service to our country.
I do have a MiG-21bis app on my phone and know about the alcohol radar cooling system. If I may use a football analogy, any given football team can beat any other given football team on any given Sunday.