Camshaft Top End Rattle

[salty_monk]

Is your exhaust sounding good & your valves set right? My 750 was making a top end rattle (sounded like a really loose valve) & I figured one of the adjusters had come loose......

Turns out 3 or 4 valves were out of tolerance at 0.2mm (spec is 0.09 - 0.13mm on this bike) plus a loose exhaust header which was amplifying the noise (I needed to snug up all bolts, I'd actually lost a couple too).

Dan

[hampshirehog]

Quick test that sometimes work - pop it in gear with the clutch in (and the motor running) and try and pull away with no throttle. If the noise stops it's your clutch more often than not (sometimes you don't even need to try and pull away). If it's still there I'd still have a look at the clutch anyway.

Just guessing here Don...but you might want to pull the clutch cover and check the large hub nut - they just love to come loose.

Hope you figure it out soon.

Thanks Ed, I hope so too.

[Nessism]

Just guessing here Don...but you might want to pull the clutch cover and check the large hub nut - they just love to come loose.

Hope you figure it out soon.

OK. I am back again with another update.

I have removed the tacho drive gear from the valve cover. Started the motor and the noise is still there. So I have determined the noise is not the chain touching the valve cover, it's not the tacho gear being too deep in mesh with the camshaft skew gear. I am 99% sure that it is not the cam cahin tensioner, it seems to be operating OK.

In fact now the noise appears to be coming from the bottom part of the engine towards the rear, around the clutch or transmission area.

I have taken another video, not for the pictures but more for you to listen to the noise. As I moved the camera around the motor to get the microphone close to different sections of the motor to pick up the noise some of the video is out of focus. Don't worry about that, just listen to the noise.

This video is with the tacho gear removed from the motor. Maybe those interested couild compare the noises from this video to the previous videos that I did and see if they can pick up any differences. is the noise getting louder or quieter.

And thanks Javelin for your comments. All appreciated.

Also to Ian for his continuedadvice and support.

http://s226.photobucket.com/albums/dd105/donclifton/Engine%20Noise/?action=view&current=P1000351.mp4

The noise to me seemed to be loudest when the camera was under the carbs and above the transmission. What is there in there that could make this noise. The clutch works great, the transmission shifts beautifully, there is no power delivery problems/noises to the rear wheel.

Thanks to all.

[ddaniels]

OK .. must be a Kawasaki trait then!

Yep, a lot of my fellow GPZ owners had tensioner problems that manifested in top end noise. Most of them put manual tensioners on.

No it wouldn't. I tried a manual on mine and no change. Incidentally, I also tried retarding the timing, but no change there either.

OK .. must be a Kawasaki trait then!

[ddaniels]

No it wouldn't. I tried a manual on mine and no change. Incidentally, I also tried retarding the timing, but no change there either.

Hi Don. I've been following this thread quite intently. I have a GS750 (in progress) which I'm 95% sure has cam-endfloat issue, but all the ideas here have me thinking of other, easier things to look at. BTW: I've also got a GS550 which I ride regularly and thank God it's as quiet as a church mouse. I'd hate to be going thru all your trauma.
However having said that, I've only recently re-ringed an '82 GPz750R1 which also was aflicted with a weird noise which had me very concerned. I too had the camcover off grinding down bits to see if the issue was the chain hitting. In the end, I found most of the noise was related to a junk tensioner and replaced it with a manual one. I've always wondered if a manual tensioner would help cam-endplay on the GS engines?

Don, your sound clip seemed to indicate that the noise was coming from the front of the cam cover, in the exhaust cam region.

You can try removing the driven gear, to see if it makes any difference.

I had a look at the contact pattern on my spare 850 gear. It's a little narrower in width that what yours shows. That means that yours had a tighter clearance than mine, which could be the cause of your noise. I's worth investigating.

Thanks for the encouragement Ian, I will have a look at it today if I get time. Cricket season is starting today and I am umpiring a game, so time will be tight, see how I go.

Thanks again.

[49er]

Don, your sound clip seemed to indicate that the noise was coming from the front of the cam cover, in the exhaust cam region.

You can try removing the driven gear, to see if it makes any difference.

I had a look at the contact pattern on my spare 850 gear. It's a little narrower in width that what yours shows. That means that yours had a tighter clearance than mine, which could be the cause of your noise. I's worth investigating.

Your tacho driven gear is mounted in the cam cover so it will rely on the correct thickness gasket for the gears to mess accurately.

Yes, that's right Ian. That's why I asked the question. Does the noise sound like that to you. What are your thoughts.

I might try putting an extra gasket in there or maybe just remove the tach drive and see if the noise disappears.

[49er]

Your tacho driven gear is mounted in the cam cover so it will rely on the correct thickness gasket for the gears to mess accurately.

Have you tried using 2 valve cover gaskets to see if the noise changes. It doesn't seem normal for the chain to rub on either side of the rubber block in the middle of the valve cover. It's almost like the cover is pushing down on the chain in the middle...Just a thought.....Billy

Thanks Billy, I have been a bit distracted lately with things. I need to do some of the things different people have suggested. I need to re-read the posts. Thanks for reminding me of this.

I just had another quick thought. Could it possibly be the tacho drive being too deeply meshed into the camshaft skew gear.?