572xp missing piston ring!

[WindsorLC33]

Hey all! So I've been tinkering with a ported 572xp that I bought last year or maybe a little bit longer ago. It's not from a builder not on here, but a known builder. I tried to contact him but haven't heard back.

Long story short.... I was having running and idling issues. I thought maybe an air leak, so I vacuum and pressure tested the crankcase...it passed. Before I blocked off the outlet of the cylinder, to do a pressure/vac test I looked in to see how the piston looked, scored etc, looks fine. Blocked everything off, tested. Good. Now when I took the block off plate off, I again looked in there. Not sure how I didn't see it/notice before... But there is no bottom ring?!

So now there's alot of questions on where did that ring go? Was it ever installed? Was it left out on purpose? Is it in the saw somewhere?

Come to find out my issues, I think are from a leaking nozzle in the carburetor... I think.

Any thoughts or input are appreciated!
Steve

 

[Funky sawman]

Common practice. I've built many 2 ring saws myself and excluded the bottom ring. Less drag, not much compression loss and less weight= higher rpm. Also seem to wear out cylinder less with one ring

 

[WindsorLC33]

Thank you for the info. I was just wanting to make sure....when I saw it, I had a moment of oh f&#+!