I got an induction tach before I messed with the tuning. That was the only way I felt comfortable messing with it. My first try at tuning my Ryobi and without the tach and I just couldn’t tell how high was too high. Didn’t want to make a mistake on my milling saw.
I ran the first 20L at 25:1. I’m running 32:1 now. I personally don’t think that mix ratio is as important as heat management. I knew from the beginning that I was going to be running right at the maximum capability of the saw. I wanted to give it every chance I could to keep it alive.
It’s worked well. no real carbon build up. I think it’s harder to build up when it’s decently tuned and run at WOT for 10 minutes straight at a time.
Ouch, can that hole be fixed? I broke off a few flywheel cover bolts because they kept backing out and I got a bit overzealous. I increased fuel mixture on my saw until it started "four stroking" after exiting the wood on a cut. I tried an induction tach, but mine was way too slow and I still killed a different saw tuning too lean with it. Tuning by ear seems to be working better for me, when usually it does not.