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I have a 550cc ZR550 - inline 4 Kaw. So I took apart my clutch (although I didn't get the basket nut off, I can in a few days), and discerned that the clunking noise is not from the clutch. I think it's a chain. It sounds like a grinding/clunking sound, which seems to me like a chain. It's RPM related, not tire speed, and it's more audible at lower RPMs, although that may just be due to engine noise.

All I can think of is the cam chain (oh god no, please???), which I'll check in a few days for tension (take off valve covers). I took out the tensioner and it seems fine, although I was a bit confused over whether or not i installed it right, there were no changes before and after inspection.

Here is a small file - an audio clip to hear what a cheap digital photo camera thinks it sounds like. In fact, it does not sound quite so bad simply because of the frequency response of this camera's mic, but it captures the bad part of the clunking well.

I moved the camera around so you get different listening angles. At first its a few feet away. Halfway through I move out 5 feet, and then I get close at the end and hit the kill switch.

-SO....any suggestions for things should I check? Thanks!

CLUNKCLUNKCLUNK!

If it's following RPM and not road speed, it's in the powerplant. Cam chain is a strong contender, but it could be a sticky camchain adjust or even worn primary drive gears (I assume the primary is gears, not chain, but if it is chain, thats another good spot to check).

Got a service manual? You will probably have use for one soon.

Yes, I have the manual. As I said, I took out the cam chain tensioner, but I don't exactly know what it's supposed to act like in my hands. I could push the thingy in, and it would spring out, which I assume means it works, however I didn't really figure out how it does what it does.

I also think it sounds like the cam chain.

I believe the ZR550 uses the old air cooled inline 4 engine from the old KZ550. Those had problems with the automatic cam chain tensioners. Most commonly, the spring would get weak and they wouldn't do their job properly. The common fix for that on the old bikes was just to replace the automatic tensioner with a manual one. Here's a good website that descibes cam chain tensioners :

http://www.dansmc.com/camchain_adjust.htm


You might also check on KZRider.com. The question of cam chain tensioners on the old Kaw inline engines comes up often there.

I wouldn't continue to ride it while it's making that clunking sound. If the cam chain jumps a tooth, you may end up with much more expensive problems to deal with.

Good Luck!

Ok, so a long chain of unfortunate events have occured which prevented me from starting my bike this morning, however I have to say that my tensioner seemed to be siezed....at the most extended length possible - is it possible that damage has occured this way?

It was working ok after I fiddled with it, and then it crumpled in my hands - which prompted me to rebuild the entire thing, which I did and now it works and was seater properly. We'll see what happens with the noise....pray....pray.....pray.

Put it back together, started it back up...no change. The tensioner is working for sure, and the sound is still there. I'll take of the valve covers and actually look at the chain, but I'm annoyed now. It makes the noise in neutral plus all gears which makes me think it's not a gear issue, and it makes a final clunk when the engine is shut off.

OK, new sound. When I started it up I revved it as normal, but when I let off the gas I heard a sound that to me was like a slipping chain sound, and although the bike kept running fine after I revved it twice, I shut it off after that. I need to fix this problem.