Cam chain noise

[scott s]

I have an '82 CB650 engine in my '72 CB500. It has what sounds to me like some cam chain noise.

Adjusting the valves and the cam chain don't seem to do much to quiet it down.
I've done the full 3K mile tune-up; checked timing (custom ignition for the engine swap), valves, synched carbs, etc., etc.


If it is the chain, is the adjuster usually OK? Is changing the chain a big deal? If I can get someone that can break the chain and rivet a new one back together, can it be done that way? Or does the engine have to come apart?

[usbear]

1) Chain Replacement not that bad and requires a chain Brake tool, which also sets rivets. No Problem, just effort.
2) Check Chain adjuster by tapping on the adjuster mechanism when you loosen adj bolt.
Sometimes worse after adjusting because of sticky adjuster, as in- it will not take up the slack because it is stuck in position and must be dislodged.
3) Check Chain Slider see if it is wore out, if it is then pull apart to replace but engine can stay in frame to do that, just remove the head bolts.

[cb650]

Did you ever make sure the adjuster is in right??????

[scott s]

CB650, unfortunately, NO I have not checked the adjuster to see if it's installed correctly. To do that would require removal of the engine. I could try removing the exhaust and the sump, but even then I can't be sure I could see what I need to see.

I have ZERO evidence that this engine has ever been apart before. I'd love to check that tensioner, to please you and for my piece of mind, but that would require removing the engine.

[scott s]

If the tensioner IS installed incorrectly, how far down do I have to take the engine to correct it?

[scott s]

Well, after looking closely at the pics and wishing very badly that it wasn't so, I believe that CB650 is right: I think the cam chain adjuster is installed incorrectly.

This pic is from another thread and shows the adjuster installed WRONG.



This is a pic of my engine that I took while it was on the engine stand. I didn't know about the tensioner deal at the time and didn't know to check. The picture is dark, but if you look carefully you can see what looks like the end of the tensioner. About 9 o'clock, just above the gear and below the bolt at 10 o'clock.

http://i190.photobucket.com/albums/z189/uberkafer/CB650/P3040080_zpsdcda8ee7.jpg

How much tear down is involved to get the tensioner where it belongs?

[cb650]

Copied from my post in sohc4



Pulling the sump is the only sure way. Maybe a scope through the clutch cover?
To get it in the slot with the head on you almost have to bend it. not drastic but just a little re curve to make the bolt clear.