Valvetrain and Starter/Transmission Noise

Hello all,

I am new to the forum. I recently purchased a 1981 KZ1100 (I believe A1 not sure how to verify this?). The PO did not take great care of the bike and I have been doing maintenance where needed. I had an oil leak on the exhaust side near the number one cylinder camshaft end plug so I replaced all the rubber end plugs and valve cover gasket. While I had the valve cover off I decided to check valve clearances. All were in specification except the intake on the number one cylinder. I replace the 2.75 shim with a 2.65 shim to bring clearance to 0.004. Also, with the valve cover off I installed a APE cam chain tensioner as the original was leaking. After reassembling everything, I have put about 50 miles on the bike. I have since noticed a metallic pinging noise near the number one cylinder intake valve area. The ping increases in speed and noise as the bike warms and revs increase. I am confused as this is the valve I changed a shim on to bring it into clearance. Any ideas what would be the source of the noise I am hearing?

The second noise I am trying to source the problem for is located near the starter motor and transmission area. I have read on the forums about the starter clutch bolts loosening and causing a strange noise. Although this noise seams similar in nature, it almost seems to be originating from the transmission area behind the starter clutch. Any ideas about this issue?

I have videoed both of the noises that I am describing. The transmission noise is quite a bit louder that the valvetrain noise but I have shown the difference in noise between the other valve areas versus the one in question.

Here is the link to the video:

Any help or advice on these two issues would be appreciated!

Thanks,

Keaton

Well, it's hard to say... Exhaust leaks at the header gaskets can sound a lot like valve ticking, so it could be that. However, properly adjusted valves do make noticeable ticking noise, especially when cold. Is the clearance on the other valves at least as wide as the one you changed? You might want to open it up and re measure.

The other noise sounds a bit like rod knock. Hard to tell because you didn't rev it up much. It could also be that the cam chain is too loose, since you changed the adjuster (and as I read it you're saying that the noise only appeared after you did that). All the OEM automatic adjuster should need to cure the leak is a new o-ring. It's pretty easy to reinstall the stock adjuster and see if that cures your issue.

You need to sync your carbs. The oil staining around the carb holders suggests they are leaking too. The engine is "stumbling."
Steve

I have read a lot about exhaust header leaks. I have felt around the headers and do not feel any air movement, but I may try changing out the copper crush gaskets anyways. The other valve clearances range from 0.002 to 0.004. As far as I can tell from the manual I didn't see where the valve clearances all needed to be the exact same just within 0.002 to 0.006.

As for the other noise, it is noticeable right at the transmission area. If I place my hand on the transmission cover I can feel that rattle noise. If I place my hand on the alternator/starter clutch area I cannot feel the rattle and it is not as loud. The rattle is more noticeable at idle and low engine speeds. As for the cam chain adjuster, the noise was present before I changed out the original for the manual adjuster.

swest-

Do you believe the pinging noise is associate with unsynced carbs?

Out of sync carb's creates a lot of shock and stumble rattle noise through the clutch assembly and starter gear stuff.

I hear both noises. Sounds like a loose cam chain, or possibly a broken chain guide. Recheck your tension.

Bottom end noise sounds bad, could be the stator magnets broke or something like that, loose bolt somewhere, otherwise its rod knock...

It will sound like that if the carbs are way out of sync. As said the PO didn't take good care of it. Be careful with that manual adjuster if it's the APE verity.
kzrider.com/forum/2-engine/599660-ape-ca...djuster-leaks#690404
I'd take the adjuster off, put my finger in there and see if the guide is sloppy. HY VO chains are tougher than the early roller chains but a broken cam chain will make for a F'ed up day and a lot of money.
Steve

Well hopefully the issue isn't rod knock. As far as I'm aware if there is rod knock the whole crank has to be replaced since the rods are pressed on. Is this correct? Is the engine salvageable if this turns out to be the case? I will purchase a carb synchronizer kit and work on that route.

Steve - I don't really understand the picture pertaining to the APE tensioner. Could you elaborate? I may go back with the original tensioner. When you are talking about taking off the tensioner does the engine need to be TDC for this procedure? By sloppy do you mean side to side movement?

Thanks,
Keaton

I doubt it's a rod knock. Yes, put it at TDC, take off the adjuster and see if the guide moves from side to side up and down. I dodged a bullet when I decided to put in my new H/C pistons and found DAMAGE. :whistle:
Steve
kzrider.com/forum/2-engine/597654-poser?start=80#690209

Does the knocking sound diminish or disappear after warming up? Can you hear it throughout the rev range, or only at idle? Does raising the idle get rid of it?

If you remove the wire from each plug in turn and ground it, does the knocking go away when one cylinder is disabled?

There's a neat trick for confirming rod knock without disassembling the motor, and that's to pull the plugs, crank the engine over (by hand) to TDC on a cylinder, go PAST TDC a bit, then put a screwdriver in the spark plug hole and press down firmly on the piston. If you're able to move the piston this way, then that's the cause of the knock.

:whistle: