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DB-Killer Squeak

12K views 56 replies 6 participants last post by  Lucian 
#1 ·
Installed my Zard Zuma Special Edition Dark Exhaust and there's a squeak coming from the pipe when I hit the throttle. Haven't actually ridden it, just testing it out in the garage...idle is fine, hit the throttle and there's a high pitch squeak. (not continuous, just intermittent squeak)

I can confirm it's the db-killer because I took it out and tested...no squeak.

I can get the db-killer to move slightly with pressure from my hand, it moves maybe 2mm and sounds like a click in any direction, so I tried readjusting it by taking the snap ring out and back in...didn't change anything.

Before I permatex the darn thing I would like to see if there are other people, other than Bob from this forum, whom I've been in contact with with a similar experience, expect he glued it.

Maybe someone has figured out another solution? I know I can remove the db-killer but I'm afraid that will be too loud.

Thanks.
 
#2 ·
Hi Pepi,

I've had exactly the same issue. I suspected it was a faulty db killer and contacted Zard who unhelpfully suggested the squeak is normal. I have a seen videos on YouTube of the same exhaust also on a DS with dB killer fitted and no noise so I have a hard time believing this.

A very kind local garage helped me out with it lately but tldr we didn't solve it

Suspecting it to be too loose we tried packing it a bit with some silicone between the backplate of the dB killer and the pipe proper. No joy.
We tried, just for science, turning it the wrong way around so the thinner part goes in rather that pointing out. Whilst this killed the bass of the exhaust note there was no squeak, which makes no sense to me and the plate is fitting in the exact same manner but only the tube part is different.
We tried cutting down the tube part a bit suspecting it could be how the thinner end was resonating. No joy.

My last trick is to try some gorilla tape around the edge of the plate and maybe on the circlip too in the hope that the rubber like texture eliminates the squeak which I think is caused by metal on metal vibration. I don't want to permatex mine in because I want to be able to keep the option for it loud and nice but also to fit the dB killer for longer rides/tours.

I'm going to have a shot with the gorilla tape and see what's up, I'll report back here in a few days so don't glue it in just yet

Hope that helps
 
#3 ·
Thanks, I appreciate your response and efforts. Definitely not normal since some videos you can hear it while others you can't. There's a DS on youtube where it produces some sound, very similar but that one sounds more like a chirp instead of squeak.
 
#4 ·
I wonder if there's an option to get a different snap ring or coat the snap ring in some high heat resistance substance that will eliminate the metal to metal contact and also provide the snap ring with a fraction of a millimeter thickness to make the seal between the db-killer plate and snap ring tighter?
 
#9 · (Edited)
Yep, that's the sound, though from what I can hear, yours may be even more lose than mine. I have to hit the throttle to get it to make that noise...in any case, let's figure it out!

I think I'll buy some high heat tape, tape the flat part of the DB, then cut through the tape exposing the hole.
 
#7 ·
Maybe use the Permatex to adhere some aluminum foil to the back side of the baffle plate? You could build up layers as needed.

-Bob
 
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#8 ·
Cheers Bob,

I actually got 'loaned' some aircraft grade aluminium tape today. I gave it a test but it wasn't a good test as I didn't have the circlip pliers to fit the circlip in to secure it but just holding it in place was creating a higher pitch squeak than before. I'm hoping the rubber tape had more damping to it but once I get the pliers back I'll try both separately
 
#10 · (Edited)
I have a Zard slip-on on my Icon. Had the same squeaking sound. It sounds like a Volkswagen Beetle. I reversed the DB killer and put it in backwards. That stopped the squeak but made the exhaust louder, however not as loud as leaving it out altogether. The solution I have now is... the DB killer is in right side out and I super glued some stainless steel kitchen pan scrubber pads around the hole, just filling the space there. I don't know how to describe them but they are stainless steel wool balls for scrubbing pans. Buy 'em in the kitchen section. Anyway, I stuffed one into the end around the hole and the squeak disappeared. :) I don't believe the squeak comes from any loose fit or metal on metal... it is supposedly just the sonics of the design. Altering the shape changes the sound and removes the squeak. If I pack the scrubber too tightly it still squeals. Some of the stainless wool has to be higher than the hole by a millimeter or so for the sound to disappear.
 
#12 ·
I may try putting it in backwards, nose in, if it's only a bit louder than nose out? Thanks for this info, that it's not due to the metal to metal contact, which is rather strange that Zard would develop a db-killer that produces this type of unfavorable sound?

Kilt, the kitchen steel wool is not flammable? Able to withstand the heat of the pipe?
 
#16 ·
xPepi and Braap.... I am out of the country so can't take any pics of my steel wool solution for you, sorry. The steel wool is not flammable. I've had it in for 8k kilometers. The steel is quite thick. Pic attached. You can buy them almost anywhere / Home Depot etc.. And putting the DB killer "nose in" takes about 30 seconds so it's easy to experiment with that.
 

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#18 ·
Basically you want to change the shape of the final exhaust hole somehow. I used Steel Wool. There are probably better ways to achieve the same thing. Put a bolt across the opening or something. I'd love to hear if you guys come up with any other solution.
 
#19 · (Edited)
I was thinking the unwanted noise was the baffle moving around because of loose tolerances. I used Permatex to anchor mine and don't have the squeak/rattle any longer.

That's why I suggested using the Permatex to the back of the baffle plate. The intent was to make it, the baffle, thicker so it wouldn't move around.

Yeah, I "glued" mine in with it, but if you put on a nice, thin, even coat of the Permatex and let it cure before reinstalling the baffle, does the sound go away?

In my case the baffle was loose. I could turn it and rattle it up and down with slight pressure. I'll have to see how easy it is to remove now that the Permatex is also holding it on.

-Bob
 
#25 ·
Damn thing still chirps after the above test. I decided to glue it in like Bob above.

Kilt, when you get back home, could you please take a pic of your pipe so I can see how you have the kitchen pan/pot scrubber placed?

Thanks.
Thanks for disproving my theory. :)

I haven't tried to remove mine yet.

-Bob
 
#24 · (Edited)
It's going to be six months before I'm back home... but trust me, I did a lot of research... it's a result of the shape of the final exhaust hole, not because metal parts are loose. Just change the shape of the final output somehow. My steel wool is placed in the indent around the DB killer, but it MUST be higher than the hole in order to change the "shape". Just by a millimeter. You don't have to glue it in to do the test. Buy some and stuff it in there loosely and listen. Change how hard it's packed and listen again. The squeak will go away. OK... attached is a diagram where I placed it... Try that and then if you can think of another way to change the shape, try that also and let us know.
 

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#28 ·
I noticed after a ride today that I still have a squeak. It's subtle, but still there.

-Bob
 
#30 ·
I have not done anything other than glue the baffle in place. In my case I could hear rattling and squeaking at idle. Using the Permatex sealant on the baffle fixed that. But, yesterday after a ride, when I pulled into the garage I heard it when I blipped the throttle. Of course I wasn't wearing earplugs or helmet at the time.

-Bob
 
#31 ·
I'm actually used to the sound now...my dad asked me if I have a valve that opens/closes as I hit the throttle...that's what it sounds like...it's not too bad. I'm still hoping to get the other baffle from Zard to see how it differs.
 
#32 ·
Yeah, I'm not going to do anything about it.

-Bob
 
#33 ·
Installed the new db-killer they sent me...the one with the flayed out end...and of course squeak is gone but it also sounds sooooo much nicer compared to the stock db-killer. I emailed them this info and suggested they ship out the zard zuma with the flayed out db-killer instead...what a difference...contact them and request one. They sent it free of charge.
 
#34 ·
Interesting. Can you post a picture of the different design?

Thanks,

-Bob
 
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