my 02 roadking has a loud knocking noise coming from the rear jug and it is top end noise, it will knock for about 1 min until it warms up and after you let it sit for a half hour or so it will knock for a few seconds, the bike has new lifters cam bearings oil pump, cam shoes ect, this problem was here before and it went away for about half a season and now it is back , anybody had this problem? any sugestions?