Hi all, I just bought a 1.20SC from a friend and it is a strong running engine. I am not familiar with tuning a YS with an idle mixture though. This is new to me, I have several (5) YS 1.20SF engines with no low speed mixture adjustment. Just the brass regulator screw on the pump regulator.
The engine seems to run fine, but there are a lot of air bubbles in the fuel line from the pump to the carb at idle speed. This engine has a shady background and no paperwork to support tuning the mixture. Shady in that it survived a home shop fire.
That is why there is no smoking in my shop.
I would appreciate any information on tuning this engine properly. It is a horse and I like it. Just want to know I have no messed it up some how.

Bob
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