Rattle at 2000rpm

2wheelsalllove

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So I bought a 96 nighthawk cb750 with 15999 miles and put about 2000 on her and when I get to about 2000 rpm I hear a rattle but then goes away after 3000 rpm tried using the stethoscope trick with a screwdriver and can't hear ticking at idle besides the valves moving I've replaced the oil and took the valve cover off chain seemed tight and not loose and valves where opening and closing so no stuck valves I put sea foam in the oil and gas tank have done it with car engines to help with rattle and clean up the insides the rattle went away for about a day till I went out for 5 plus hrs on her and it came back so I did another oil change and it's still there I haven't synced the carbs yet and the pervious owner said he never touched them and was wondering if that could be my issue I know these old honda bikes tend to have a slight tick but even new bikes do but this is a loud ticking noise and I cant seem to figure it out she starts just fine and has no power loss up hill or on a straight but I just can't figure out what the noise is any help would be nice
 

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Do you have an external fuel filter under the tank rattling against something? Maybe one of the throttle cable nuts loosened and is rattling. I'm just spit balling
 
I've gone through from front to back with all the plastics off even the tank no loose bolts or anything hitting anything and it's definitely coming from inside the engine
 
I have an idea about your rattle. Please look for an 8mm, short, six pt. 1/4 drive socket, maybe trapped between the frame and the coils. Or, maybe the same socket is trapped near the rear of the starter cover. If you find that sucker, message me and I will give you my address so you can mail it back to me. I just knew it had to go somewhere! Thanks
 
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