Don't know, the only DA50 I ever saw was one of the first, sent to me by Dave himself..I was not overly impressed at the time, maybe they made some changes...I recall the rpm was not a whole lot more than the Poulan 46 I was converting at the time...I even made a post, "who needs technology" comparing the DA to the Poulan....It's in here somewhere, about 4 years ago...