Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!genrad!decvax!harpo!floyd!garry From: garry@floyd.UUCP Newsgroups: net.auto Subject: engine backfiring Message-ID: <1695@floyd.UUCP> Date: Tue, 28-Jun-83 15:38:22 EDT Article-I.D.: floyd.1695 Posted: Tue Jun 28 15:38:22 1983 Date-Received: Tue, 28-Jun-83 22:21:31 EDT Lines: 10 backfiring under deceleration is often a symptom of innacurate ignition timing. if the timing is too far retarded it will cause this. what happens ( i think ) is that the spark fires too late to burn all the fuel/air mixture before the exhaust valve opens, so some of the combustion is taking place in the exhaust pipes. i had this problem with a 1970 bmw 750 motorcycle, and a good tune up, including setting the timing, fixed it right up... garry hodgson BTL whippany floyd!garry