Just because RATCHET chooses to avoid fighting doesn't mean he never learned how. His intimate knowledge of anatomy allows him to strike with surgical precision, making a fight against him a very painful losing proposition.
AUTOBOT RATCHET has dedicated his life to healing the sick and repairing the wounded. Every weapon he has ever carried has served a dual purpose as both a means of defense and a rescue tool. Even as he battles the DECEPTICONS, his mind works overtime to process the most efficient means of saving his enemies lives once the battle is over.