I thought R50 was one of the better ones not having castor oil. I think it's the castor that really did it. Carbon plated piston anyone? I recently switched to R50 after finding out the other oil isn't for long term work stuff. It definitely wasn't tuned rich. I've also wondered if Klots burns my eyes or if regular exhaust will do that, and such a big saw put out so much exhaust that my eyes sometimes burn and water.
Thanks, I think I'd notice the clip during rebuild. I did notice they had ears when looking through the pics, and it got me wondering.