Home » Blog » 300 » 2019-2020 RXT-X 300 – These Things Are Fast! Get yours tuned today. 2019-2020 RXT-X 300 – These Things Are Fast! Get yours tuned today. June 8, 2020 Martin 0 300, This machine did 79MPH with just our primary 300 performance tune!Previous: Reliable Tuning links up with American Jet ConceptNext: New OEM Parts Website!About The Author Martin Leave a Reply Cancel replyYou must be logged in to post a comment.