Had an indy shop rebuild my 88" 01 Ultra to a 97" using Rev-Tech cylinders and pistons, put a Woods TW-5G 575 lift cams with Woods directional lifters, and had their machine shop take the heads and instal 1.94 intake valves and 1.62 exhaust and S&S beehive valve springs and cc the combustion chambers to 85cc's. When you first start the motor, it is whisper quiet, even more quiet than stock, but as the oil warms it starts to rattle extremely loud. Never gets worse, but it's almost embarassing when sitting at a light. Switched from Amsoil 20-50 synthetic to Spectro 20-50 dino oil at 250 miles and it doesn't make a differance. They've listened to it twice and tell me it's not too bad as have a few others, but i wonder if anyone can give me any ideas on where to start my search. Thinking as metal warms and expands causing something to touch but sounds more like a loose pushrod, even tho we've re-set them twice. Wonder about shimming rockers, if that would help. They shimmed one but not the others.