always ALWAYS adjust the chain at the tightest spot. if you have a stand, lift the rear then spin the tire. look at the chain in relation to the swing arm. you will be able to see when the chain is tight. find that tight spot - the tightest spot if more than one - then set bike down and adjust. the service manual says 20 to 30 mm deflection. i say just until the chain barely touches the swing arm when pushing up on the lower loop of the chain. speaking of chains, vera lynn is on her side stand waiting for me to whip one on her. was riding cinnamon girl and guess what, yup she is going to need one soon. 18000 miles happens real quick. dangit. chains and tires. i could only imagine the cost if i had a couple of triples
regarding the rattle at wot, be sure to check all your exhaust connections.