Yes — a 6 oz gasoline fuel system cleaner (like Chevron Techron or Totachi Moto) can be used in 2‑stroke engines, but only if it is specifically labeled as safe for mixed fuel/oil systems. Products such as Techron Complete Fuel System Cleaner and Totachi Complete Fuel System Clean Moto are explicitly formulated for both 4‑stroke and 2‑stroke gasoline engines.