Last year I found this web site and asked for advice about purchasing a 1978 Odyssey with 93 original miles that had been garaged for 23 years. Your responses were very helpful. I've had fun with the bike. We keep it in an unheated shed at our cabin and after the winter it started up fine. Over this weekend it started to make a knocking sound when I tried to start it. My husband got it to run and after the engine starts the noise stops. I got a copy of the manual by writing to the manufacturer last year, however, at this point we don't have a clue what is wrong with the bike. Does anyone here have an idea what the noise might be?