strange knock and i do not know were to start

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pan57
Posts: 32
Joined: Mon Jul 16, 2007 11:25 am
Location: Baton Rouge, la

strange knock and i do not know were to start

#1

Post by pan57 » Wed Jun 18, 2008 5:00 am

hey guys i was doing a final fluid change before heading out on a 2500 mile treck and when i started it i heard a knocking and not being a very good diagnostition i am not sure where to start. it sounds like it is coming from the front jug so i will start by pulling the heads to make sure the heads and the jugs look ok. the bike has about 1k miles on it and both the top and bottom are fresh rebuild. any suggestion would be appreciated.



john HD
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#2

Post by john HD » Wed Jun 18, 2008 11:10 am

if it sounds like a tappet making the noise, try cleaning your tappet screen before you take the motor apart.

john

pan57
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Joined: Mon Jul 16, 2007 11:25 am
Location: Baton Rouge, la

#3

Post by pan57 » Wed Jun 18, 2008 12:10 pm

I did clean the tappet screen while i was changing all the fluids. but that did give me and idea to pull the push rods and tapppets before i pull the heads juuuust to make sure. thanks

57pan
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#4

Post by 57pan » Wed Jun 18, 2008 6:18 pm

Get a piece of garden hose about three feet long. Put one end in your ear and move the other end around the motor while it is running. Try it. It works! You can really isolate sounds this way.

biker_k
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strange knock

#5

Post by biker_k » Wed Jun 18, 2008 7:35 pm

I had a strange knock happening too. Turned out to be a stretched primary chain. If the knock is low in frequency and loud, it might not have anything to do with your top end. If you are running a chain primary without a compensator, then there is a good chance your chain has stretched and is knocking on your tin.

51Hog
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#6

Post by 51Hog » Wed Jun 18, 2008 7:39 pm

57pan wrote:Get a piece of garden hose about three feet long. Put one end in your ear and move the other end around the motor while it is running. Try it. It works! You can really isolate sounds this way.
Garden hose works great. I use the long screw driver and put the handle to my ear. Sounds a bit different than the hose.

windweaver
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#7

Post by windweaver » Sun Jun 22, 2008 12:22 am

wooden dowel or an old wooden broom handle cut down. works for me. WW

dromie
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#8

Post by dromie » Mon Jun 23, 2008 5:44 pm

Check for an exhaust leak on your front head...

A pin hole leak will sound just like valves tapping! The clicking may also disappear or get worse at different engine temperatures if it's a exhaust leak.

So, if after listening to you valve covers with whatever method you choose, they both seem to sound the same, it is likely an exhaust leak.

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