Nah, most push and riding mowers are definitely 4 stroke. You’re absolutely correct that 2 strokes need to burn oil and create some visible smoke (to be properly lubricated). Only small, powered equipment (such as trimmers, blowers, and chainsaws) are still commonly made with 2 strokes. My smoking push mower was made in the mid 1980’s and is miraculously still running. It apparently has worn seals that are allowing crankcase oil into the combustion chamber.
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