aldot, if you use the correct oil to fuel ratio and a decent spark plug, it shouldn't smoke once it burns the carbon out of the muffler. There is a guy lives near me who runs an old Victa wreathed in blue smoke - it must be 16:1 or worse. He's happy, and he gets the lawn mowed - but whoever inherits that old mower from him will have a horribly carboned up exhaust port and muffler.
