Rattle when idling down on xj550

I'm puzzled about this rattle when my engine idles down after I rev it. But once it hits low idle it stops. it seems to happen right around 2000 rpm or so. I thought it might need a valve adjustment which it did. But that did not solve the rattle. I've checked the exhaust and doesn't seem to be that. It sounds like it is coming from the front of the engine. I checked the cam chain tension and it seems fine. I have no idea what it could be. It runs perfectly fine beyond that though. I just don't want to be wearing out something or doing more damage by ignoring it. Thanks, any insight to this problem would be helpful :?

 

only rattle I get is from my windshield vibrating on the rear of the instrument cluster. have you double checked the exhaust headers to be certain they are fastened? is it more of a rattle like something loose or just a vibrating noise like the engine is happy? lol

 

It's almost like a winding rattle. I haven't checked the header bolts though. I will check that for sure.

 

You sure you're not hearing the clutch/trans rattle from the primary chain going slack as the revs fall?

If so, that's normal.

 

I suppose that would make sense fitz. It kinda sounds like its coming from that area. It sounds as if a chain is going slack and vibrating something. At first I thought it was the cam chain getting loose.

 

My Maxim-X did sound the same at idle when the carbs were out of balance.

 

When you say out of balance do you mean out of synch?

 

Exactly.

 

Also using good fresh moto oil will tend to calm down that primary chain/trans rattle-it did with my 550 but not really until the 3rd oil change and almost 2k in miles.

To pin it down you could have someone rev the motor to make it happen while you probe around with a piece of pvc pipe held to your ear and move it around until you can dial in the source (or area) then you will know if it's loose parts or internal. The most vibes come in around 4-5k so if it's not doing it there then it probably is your primary and not something loose.