Rattle on 400ex
Did you ever find your rattle? I have a similar rattle on a 400ex. My rattle stops when I put my boot on the heat shield. The rattle is still there when I ride without the heat shield and I tightened the header bolts on the exhaust. The rattle is loudest about mid throttle and is really loud when I use the engine compression to slow down. Just return from Rockhouse trail system in WV and the rattle was really loud going down hill.