Well, I got news of my first saw failure yesterday - an Asian 440 Big Bore someone took off my hands.
Got the saw back this morning and ripped it down. The lower ring hung up on the bottom of the Exhaust port, which I did not widen, (I only widened the top)and I made sure it was beveled (both top and bottom). I also noticed that the lower rod bearing was starting to go, and I'm wondering if that caused the ring to hang up.
Another similar one I built for a Tree Pro had a lot more hours on it w/o any problems. This guy (with the failure) loved the saw, and always ran 40:1, but the 2 cycle oil he uses is not as good as the AMSOIL Saber I use. Luckily, I had another nearly identical saw I sent his way, so he will not be without. It is by far his favorite firewood saw. He has some decent sized hardwoods on his property, and says this saw goes through it twice as fast as his other saws.
So I have the following questions (comments welcome):
Is it likely that the lower rod bearing starting to fail resulted in the ring hanging up???
Did I get a bad crank, or are they all crap waiting to fail???
Will better oil keep them healthier a lot longer???
I'm hoping that some folks with time on these things will respond.
Thanks, Mustang Mike