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Discussion Starter #1
As many of you I decided to replace the original muffler with a less restrictive one, I chose this one with a decat:

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I was really happy with it; good sound, low weight, and looks nice

After some month I installed a Rapidbike Evo and a new decat pipe:



After that I realized that with the new additions I needed to put the db-killer on because with this configuration it was too noisy

A few weeks later, I noticed that the exhaust sticker was kind of fried...

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I told the distributor and he said he would send me some new stickers, but one day before they arrive, I was on the motorway and suddenly I heard a "pop" and then the bike sounded as if I had missed the db-killer 馃槗

I immediately stopped at the side, looked at the silencer and saw this:

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This is a better picture from home:

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It seams that the exhaust blew up! o_O
I never saw or heard of anything like this

I immediately contacted the distributor, sent him the damaged exhaust and then he sent me a new one.
I put the new exhaust on, and the first time I used it when I got to work (40 km) I saw that the sticker was like fried again... when I removed the sticker I saw that there was a black stain and that the fiber was as if burnt 馃槷

Do any of you guys have any idea about this?
Could it be that Scorpion sized the exhaust only for an original motorbike? If so, I think it's not appropriate, since those of us who install this type of exhaust usually make other modifications

So I contacted the dealer again and sent him the damaged exhaust.He proposed to change my exhaust for another one (it only works with Scorpion and Arrow brands), so I already received my titanium Arrow GP2.

In my free time from this quarantine I started to modify the original muffler, I hope to finish it next week.

I'll see which one I'll keep.

Then, whatever I choose, I hope it can carry the load and doesn't explode... 馃檹


Any comments will be appreciated
 

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it seems like the decibel killer is topping too much exhaust flow and it's causing it to pressurise the 'can' which is inflating it like a balloon until it pops,
is it a true Scorpion or a Chinese one
 

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Was it original DB killer?

Well, as I have heard problems before with full carbon silencers, I would say their reliability is not that great. I assume that's the reason why we don't see them in racing environment and some of manufactures tend to vinyl the steel or titanium silencer with carbon fiber, just to make them last forever.
I would ask Scorpion directly their view for this, but as your machine is tuned, I think the silencer was more meant for original setup. So if now the flow was too free (without cat + pre silencer) and gases were too hot in end silencer (resin started to melt), I assume this is the result you will get with DB killer.
I would also say you are lucky enough not to bust engine parts if there was pressure issues in silencer.

If you want lightweight option, then titanium is only way to go. If you still ever want carbon look, then search for silencers that are coated with CF, but made with steel or titanium.
 

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Discussion Starter #4
it seems like the decibel killer is topping too much exhaust flow and it's causing it to pressurise the 'can' which is inflating it like a balloon until it pops,
is it a true Scorpion or a Chinese one
It seems to me that you are right, that must have been the cause (y)

Before returning it, and because I needed the bike to make a short trip that I had planned, I modified the db-killer to make sure that it does not explode during the trip:

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I made the back hole and the last two rows of larger holes
Even though it felt better, I mean the muffler wasn't that hot and the sound wasn't that loud, I gave it back because I didn't want to take the risk

It was an original Scorpion
 

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Discussion Starter #5
Was it original DB killer?

Well, as I have heard problems before with full carbon silencers, I would say their reliability is not that great. I assume that's the reason why we don't see them in racing environment and some of manufactures tend to vinyl the steel or titanium silencer with carbon fiber, just to make them last forever.
I would ask Scorpion directly their view for this, but as your machine is tuned, I think the silencer was more meant for original setup. So if now the flow was too free (without cat + pre silencer) and gases were too hot in end silencer (resin started to melt), I assume this is the result you will get with DB killer.
I would also say you are lucky enough not to bust engine parts if there was pressure issues in silencer.

If you want lightweight option, then titanium is only way to go. If you still ever want carbon look, then search for silencers that are coated with CF, but made with steel or titanium.
I agree with you, lesson learned!

Thanks!
 

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unfortunately it's why you see many standard exhaust systems so big, they need a lot of room for the gasses to compress before they can get out of the small openings needed to keep noise down,
imagine putting a decibel killer directly into the pipe with no actual silencer can, the bike would hardly run
 

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There is a whole bunch of pressure coming out of these things, would have to be an extremely well crafted can for me to go CF..... I have the LeoVince Evo One Titanium on mine, love it. But it is also wide open and loud AF. Stand behind it and you will realize just how much air is coming out of these little engines. Reduce that to a .5 inch hole and the pressure behind that hole has to be ridiculous. Not sure the holes you drilled have much effect on the pressure behind this hole, if drilling anything this should have been where you started:
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There is a whole bunch of pressure coming out of these things, would have to be an extremely well crafted can for me to go CF..... I have the LeoVince Evo One Titanium on mine, love it. But it is also wide open and loud AF. Stand behind it and you will realize just how much air is coming out of these little engines. Reduce that to a .5 inch hole and the pressure behind that hole has to be ridiculous. Not sure the holes you drilled have much effect on the pressure behind this hole, if drilling anything this should have been where you started: View attachment 52059
For sure! When I saw my DB with similar hole, I had the same thought that this can't be right (even for 125), especially if I make the flow even better. I kept the original one for inspections but ordered the new DB killer from PipeWerx. They made one for custom specs and I just had to modify it for my scorpion (also I kept it short, similar to Akra racing DB killers). It sounds really good and has way better flow. You can see more pics in blog. Adding the missing pieces to the puzzle.

Also without the DB killer the sound with CAT is not that loud, but the low end was gone, so as my new DB killer has enough restriction, the low end came back. So I'm really happy with it. For curiosity i want to test in on Dyno, to see with option will give what results. But for butt feeling, the custom one sounds and drives the best.
 
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