My bike makes terrible hammering sound when idling

If it's broken or just needs tweaked

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Katatonia
Posts: 17
Joined: Wed Aug 31, 2016 6:36 am

My bike makes terrible hammering sound when idling

Postby Katatonia » Tue Mar 21, 2017 4:13 pm

Anyone got a clue why? I looked at the chain tensioner and it didnt help, also checkes the chain and it appears nice and firm.

https://youtu.be/NN2HZHmi6Wo

Any ideas?

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Folsoml
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Location: North Florida

Re: My bike makes terrible hammering sound when idling

Postby Folsoml » Tue Mar 21, 2017 8:24 pm

Cam tensioner could be installed wrong. Check this thread:

viewtopic.php?f=4&t=74
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cb650
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Re: My bike makes terrible hammering sound when idling

Postby cb650 » Wed Mar 22, 2017 5:19 am

does it go away when you pull in the clutch?
Did you clean the tank out?!?!?!?!

Katatonia
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Joined: Wed Aug 31, 2016 6:36 am

Re: My bike makes terrible hammering sound when idling

Postby Katatonia » Wed Mar 22, 2017 5:34 am

It mostly does, yes. Sometimes i can still detect a hammeringsound (atleast i think so) but it's way less prominant than when idling. It's only real bad like this when it goes below 1200rpm or so.

I tried adjusting the tensioner, but it does not seem to do anything good or bad. I recently had it open and changed the headgasket, and the chain looked tight and fine. (to my knowledge)

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tario
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Re: My bike makes terrible hammering sound when idling

Postby tario » Wed Mar 22, 2017 1:09 pm

For anyone skipping the video it's a 1981/82 engine... 1979 frame maybe,

I'd say check the valves just for gits and shiggles. Hopefully that was part of the head gasket replacement though. I assume you lined up the timing and everything on reassembly. There is a very detailed article you can find with a quick google search that will walk you through the valves.

I do wonder if a sticky spark advancer would cause this... anyone know more about this?
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Katatonia
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Re: My bike makes terrible hammering sound when idling

Postby Katatonia » Wed Mar 22, 2017 2:56 pm

Update, it seems to be slightly better when i pull the clutch...

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Re: My bike makes terrible hammering sound when idling

Postby cb650 » Thu Mar 23, 2017 4:41 am

Adjust it at the clutch not the cable. 650 cluches do rattle some when proper
Did you clean the tank out?!?!?!?!


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