when first starting bike , sounds great smooth ,quiet, ready to go. then every few seconds there is a sound like the timing chain rubbing on the tensioner. Ive had the valve covers off and could see no signs of anything rubbing,also replaced chain on right side of engine. oil pump drive,would love to make the noise go away.any suggestions. I was a harley davidson mech for ten years so im not a total mech. idiot.