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post #1 of 5 (permalink) Old 06-17-2010, 04:31 PM Thread Starter
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Another noise thread

I've spent a considerable amount of time trying to diagnose a "chirping" noise of sorts that only happens:

-after the bike is hot
-during decell (throttle chopped)
-usually in 3-4-5 gear
-around 4000 rpms (not much above or below)
-on the right side, near the engine, quite low

I posted questions about this in the past and have tried many different fixes.

It seems I can make the noise stop when I pull my heel firmly back against the right header pipe. I've removed/reinstalled the pipes, loosened and retightened the heat shields, loosened and retightened the header bolts, and "pryed" the header pipe away from the crash bar that it was very close to touching. I even changed to the "Harley header gasket". It seemed to become less frequent at times, but is now back again. I believe it's gotta be related to the exhaust - especially since I can make it stop with my heel.

Any other things I can try to do to the right header pipe so it doesn't resonate? I'm thinking maybe loosening the connection at the header? or removing the header pipe and squeezing the end slightly to create a [U]very slight oval , or maybe creating some test "shims" to wedge into various areas hoping to stop the resonance, change back to the Kawi header gasket?, etc., etc..

Any other suggestions? This is very frustrating!

Deaner
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post #2 of 5 (permalink) Old 06-17-2010, 05:45 PM
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Try using the old kawasaki header gasket along with the harley one. Make sure the recess is clean first. Apply wheel grease to both of them to hold them while re-installing the header.

If you have a leak making the noise, the grease will blow out and leave a mark to show you where it is. Hopefully the extra gasket will do the trick.


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post #3 of 5 (permalink) Old 06-17-2010, 05:53 PM
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Non related to exhaust, but have you checked all your engine mounts?

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post #4 of 5 (permalink) Old 06-18-2010, 02:18 PM Thread Starter
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I have checked the motor mounts but will go back and check them again. Also, Knifemaker, sounds like you are thinking it might be a leak rather than something rubbing with/on the header pipe - correct?

At any rate maybe stacking the gaskets will help for either.

Thanks for the suggestions!
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post #5 of 5 (permalink) Old 06-18-2010, 06:38 PM
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Quote:
Originally Posted by dino750 View Post
Knifemaker, sounds like you are thinking it might be a leak rather than something rubbing with/on the header pipe - correct?
Correct. It might be a leak...and if it is a vibration the greasy two gasket thing might help too.

Since you said it happens durring de-accelleration, with the thottle closed.......I would check the read valve hoses and gaskets too. Those valves open up under de-accel and might be the culprit also.
Try the "marble" trick and see if it goes away.

Blow by on a loose or worn gasket does make a "chirping" sound.


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