A few days back I noticed a strange and loud rattle coming from my bike (96 900RR). It is apparent when I'm riding in any gear from 4.5K RPM and above. It does not rattle when cursing but when I apply slight throttle to have a slight acceleration it is apparent and is quite loud. If I apply a heavy throttle it goes away. It at first sounded like it was coming from my front sprocket. I took the front sprocket cover off and verified the sprocket was nice and snug. I also looked at all the cosmetic bolts and verified they were all tight too. I also started my bike up and while parked I revved the engine and couldn't hear anything. Which I was expecting because it only seems to appear when the bike(engine) is under slight load. Anyone have any ideas or suggestions of what I should check?