Higher octane fuels supposetly forms less carbon build up. Years back made an experiment with 2 same 2 stroke Tohatsu 30 HP engines. One used regular 90 octane fuel, the other premium 95 octane fuel, both engines were run at constant 3/4 to wot speed on trasport ribs.
After 1.5 K meterd working hours, the engine using regular fuel had near double carbon built up than the one using 95 octane. Besides 95 had better throttle response with bit less fuel consumption.
Good to polish pistons & cylinder head interior to baby's arse soft condition, will form less carbon buil up. 2 strokes engines needs to be decarboned at min each 100 worked hours.
Buy a can of carbon guard, follow instructions, engine must be on while spraying product though carbs, cleans fantastic well all combustion chamber carbon deposits, engine runs smooth, with top power and rejuvenated glow.