Dave
My YS 63 runs great at full throttle at mid seems fine, but it does not idle consistently. I also find that if i gas it to mid throttle then quickly down to idle it idles at a much lower rpm than if i do it gradually. It seems to want to shut off as well. I am running ys 20/20 with ys plug. Motor has been run for about 1 1/2 gallons, and is mounteed inverted.

I am thinking i need to lean out the midrange with the regulator. Which direction do I screw it?

What do you think is going on and what info do you need to help?

BTW
I love this motor. If i could only get it adjusted correctly.