I often buy large lots of used/discarded yard equipment and fix the good ones to sell, and steal engines from a lot of them to convert for airplanes. The Ryobis, while not a high dollar, top brand like Echo or Stihl, seem to be the best of the lower priced weedeaters and consistently run pretty well if maintained properly. If it is rear intake/rear exhaust, it is actually a Ryobi engine. If it is a side exhaust/side intake, it is probably a Homelite engine which is actually slightly better.

AV8TOR