Certainly you can pray whatever you wish. In fact there are some other prayer chaplets that are also designed to be said on Rosary beads, such as the Chaplet of the Divine Mercy or the Chaplet of the Holy Wounds.
My Rosaries have been known to also do double duty as chotkis for purposes of praying the ‘Jesus Prayer’ of our Eastern Catholic and Orthodox brothers (“Jesus Christ, Son of the Living God, have mercy on me, a sinner” or similar words).
