'81 engine ticking/rattling noise


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sin486
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'81 engine ticking/rattling noise

Post by sin486 »

I purchased am '81 CBX-B a few months ago, it has been making a ticking/rattling noise from the left side of the bike which can be heard best at low RPM's. After some research, I initially thought it was the alternator but with a sophisticated stethoscope (screwdriver), the noise seems to be loudest at the engine block. Any ideas on further diagnosis? Or is this noise expected and I can ignore?

Video in which you can clearly hear the noise:

https://www.youtube.com/watch?v=AzSEKjTZt2w

steve murdoch icoa #5322
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Re: '81 engine ticking/rattling noise

Post by steve murdoch icoa #5322 »

Doesn't sound too bad to my backyard mechanic ear. The engine guys will be along.
Maybe a slight air exhaust leak. Header clamps snug?

daves79x
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Re: '81 engine ticking/rattling noise

Post by daves79x »

Sounds, too, like an exhaust leak at low idle, but above that, just normal 'sewing machine' sounds. You could quiet that down to almost zero by installing a set of oversize cam joints.

Dave

sin486
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Re: '81 engine ticking/rattling noise

Post by sin486 »

Is it possible to replace the cam joints while doing a valve adjustment - only the valve cover has to come off? I also assume that I'd only have to take off two of the four cam shafts to get the the cam joints. I don't want to fiddle too much with the chains.

The next step would be to find a supplier of the oversized cam joints.

daves79x
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Re: '81 engine ticking/rattling noise

Post by daves79x »

Yes, just removal of the valve cover and the 2 left-side cams is all you need to do. But I’d first insure your cam chains are adjusted properly and the adjusters, particularly the cam-to-cam one is working properly. Then make sure you have a shop manual for cam removal/installation.

Louis has the oversized joints here in the States, Six Center in Holland carries them also.

Dave

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