Yamaha makes a fuel system cleaner and "top end" cleaner (not a stabilizer) that works extremely well,
"Ring-Free"
https://www.shopyamaha.com/product/details/ring-free-plus?b=Search&d=34
It's made for both 2 and 4 stroke engines and is highly regarded in the Marine world. Do a search..
I personally use it in EVERY GAS machine (two strokes as well) I own as well as customers machines. Since using it (from about 2007 when I learned about it), I've NEVER had to re-clean a carb of my own.
*Often, after a repair and tune (with a tach), I re-tune the next day... Roughly, 50% of the time, I can NOW increase RPM's re-tuning, doing NOTHING ELSE.
Normal mix is 1oz / 10 gallons. A shock treatment is 2 oz / ONE gallon. I've mixed it heavier with NO issues...
