A friend of mine bought this 2005 Kaw. Mean Streak with low mileage (27,000). He rode it for about a week and then shut it off one night like normal. When he woke up the next morning he fired up his bike and it knocks. He said he was not riding it hard the night before, and the oil has been changed about 200 miles ago. This noise sounds like the rear cylinder piston wrist-pin. At first I though stuck valve, but everything is tight in the rocker box and moving the way it should. So before I break this thing down and do an upper end rebuild on it, is there anyone who has seen this before and may save me some trouble before I dig into it? thank you all very much and PS. I ride a 1981 Harley Davidson Wide Glide that is all custom by me personally. Kicker only, I tell people my kick starter is an oil primer when they ask me what it is.LoL!