New noises...

my 82 CSR 1000 started making some noise from either the bottom end or the tranny but I cant figure out where. Seems to be from the left side also. Doesnt happen when idling but happens at all speeds while riding but comes and goes. The noise is not consistent either, so I dont believe its part of any rotating assembly. Its a light, tinny sound and sounds like something is being tossed around inside. Almost like a ducati dry-clutch but totally random. Doesnt seem to be affecting ridability either. I pulled the covers off both sides, alternator, drive sprocket and clutch cover and found nada. Also checked the starter for any hang-up and it works just fine. I did a nut and bolt check on everything I could find, tightened the chain to spec and checked the wheel bearings front and rear and everything is a ok. My buddy said his brothers 1000 made the same noise but never had any negative fall-out from it. Any ideas? Im totally stumped.