engine clunk at idle

hey, I have an 82 xj 550 and the engine is making some noise. It makes a clunking noise when the idle is set much below 2k. I tried isolating each cylinder but the sound remained.

I found that when I pull the clutch lever the sound is almost muted. Its difficult to isolate but I think that it is coming from the area around my front sprocket.

Any ideas?

Oh, and the engine runs real nice except for this noise.

 

Pull the clutch and tape or tie it so the noise is minimized.

Probe the running engine with a long dowel or even a yard stick.
Place one end on various places to listen for noises ... and, LISTEN to other end of the probe.

Put your thumb on the end of the probe ... and "Listen" to your thumbnail by sticking your ear right on your thumb.

You should hear:
Rotational noises. Steady. Machine noise.
Ticking ... around the valve train.

What you don't want to hear is Knocking.
Knockin's not normal.

 

i did some listening and the noise is coming from the transmission part of the case. I cant determine whether the noise comes from the left or right side.

thanks

 

What's the noise?

Mechanical, rotational or knock?

 

I would choose knock out of the selected noises.

 

Now ... you listen and have someone pull the lead off of each spark plug ... one at a time ... and carefully listen as each plug cap is pulled and replaced.

 

I did that initially and the noise did not differ at all. Well, it got a little louder when I unhooked any spark plug because the idle dropped a little.

 

if the noise goes away when yu pull in the clutch......its probly a carb synch issue. i had that happen to me with a 85 honda v65.

 

I spent some time trying to diagnose the problem yesterday. No success by the way.

To make sure it wasn't my timing chain tensioner I removed it and inspected it. It appears to be in great shape. Stretched the spring just a bit to maybe add some more tension.

New findings. When the bike is on the center stand so I can spin my rear wheel with the trans in neutral and the engine off it makes a terrible sound behind the front sprocket. Sounds like a bunch of marbles in the case.

Can someone else with a 550 chain drive tell me if their bike does this too?

thanks.

 

well ive got a xj550 with only about 4500 original miles on it and mine also has a sorta rattle when you let out the clutch in nuetral, was told this is a common clutch rattle and not to be alarmed. Bike runs great with no issues, does anyone else have a xj 550 with the common clutch rattle?
I was curious if normal since my bike has only 4500 miles??

 

My xj550rh has over 24.000 miles on it and has the same clutch rattle.

I was told this is normal by someone whose owned a couple 550's.

 

I'd love to answer, but my 550 Maxim won't run well enough to tell. I'm workin' on it...