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Discussion Starter #5
their so cheap and built quite well. sound is normal not loud at all. it has removable baffle if you want loud. it's outrageous how much mufflers cost. here is a alternative.
looks awesome and works well on my ninja 250r too. knock off sticker included as well. nice
 

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Agreed! We are taken for a ride by the big boys!! These knock offs look and sound as good as the expensive ones.....
 

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That looks Hot.

Imagine if for some reason that the quality is sub par of the el cheapos. Also imagine how many dozen of the el cheapo cans you can buy for the price of one name brand. Insane. The costs of an exhaust system is disproportionate to what you actually get, in my opinion.
 

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Much of what you get from the big names you can’t see or hear. Anyone can knock up a pipe, especially if you copy something someone else has spent time and money developing.

Have a look at all the exhaust manufacturers who have gone to the wall including some who made some **** fine pipes. Akra have their own Dyno as do others and they have to have their pipes approved by the Authorities which isn’t cheap.

I know some don’t care but if we are having this discussion, let’s be clear that importing a knock off pipe is also illegal especially if it comes with fake stickers. The fines if Customs happen to open up your parcel will make you wish you’d gone for one of the top of the line carbon and titanium ones from the most expensive manufacturer. It probably won’t happen to you but...
 

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The costs of an exhaust system is disproportionate to what you actually get, in my opinion.

Do you think that there is some sort of mysterious juju going on inside of the link pipe and/or muffler can?? There is not!

The link pipe is, well, a piece of pipe with the proper bend, (flared attachment at one end in our case) with smooth walls inside or out, and a couple spring attachment points.
The muffler can is a can with two end caps, rivets to secure them, a decibel killer insert piece, and maybe some fiberglass and expanded metal wire mesh on the interior.
I do not believe that there is some sort of amazing research and development that costs mega dollars happening. Of course the Asian copies are just that, copies. Sometimes the materials used are inferior. Sometimes the quality of assembly is inferior. I agree that often times in life, you get what you pay for (like a fine timepiece). Not so with a motorcycle exhaust system.

Of course I would not want the sticker on the muffler can, and without it there is no crime committed. It’s just another manufacturers’ mousetrap. I don’t wear clothing with brand advertisements either.
 

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The costs of an exhaust system is disproportionate to what you actually get, in my opinion.

Do you think that there is some sort of mysterious juju going on inside of the link pipe and/or muffler can?? There is not!

I accept that is your opinion. I’ve not yet met an engineer with experience in engine tuning who agrees with you.
 

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Thank you.
If you want to accept this comparison, I would be willing to do it:

I buy the Chinese cheapo slip on, you purchase the Akropovic genuine article. We both disassemble them by drilling the rivets out and remove the contents (or lack there of), and document the process by taking pictures and posting them here for all to see.

Then, without any Engineers’ hearsay, we will have definitive proof of the similarities and differences.

This will in no way render the mufflers useless as you just reassemble with stainless steel pop rivets.
 

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Unless both are tested on the same dyno on the same bike that is a pointless exercise. I guess you will next be suggesting that a 1290 and a 390 KTM have similar performance characteristics based on the both having similar components.
 

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I didn’t think you would take me up on the offer. In other words, put your money where your mouth is. I can understand why you defend the higher priced genuine Akrapovic slip on, you bought one!!!

Do you really think there is any difference in performance gain between the higher priced name brand, than the cheap knockoff? There isn’t!!
Because all either one is, is a canister with fiberglass insulation inside that surrounds a perforated metal tube.

And stay on track Brother. I’m not comparing different motorbikes, just the different priced slip on mufflers.

Spend the money, enjoy the delusions!
 

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I was curious about modifying the stock exhaust, seems like a pretty common way to personalize your bike's sound. So straight forward it's almost scary. I know some people had issues with drilling the db killer out but it took me less than 2 min to do everything and the result was so worth it. I will still buy a cat delete and slip on at some point but for now, wow!

I think people having issues with the drilling part is because they spin the drill too fast. I used penetrating oil and drilled the part out at very slow speed. Took less than a minute to get it done and another minute to loosen the exhaust to get the part out from inside the muffler after it detached. So 1.5" holesaw, 4mm allen for the heat shield, can holder and 6mm for the donuts bolt to loosen the exhaust clamp, Voila!

I tend to agree that those canisters are way overpriced especially when their dyno posts show very marginal hp gain (0.5hp on average), if any. But copies wouldn't exist without the originals so I don't mind to support originals as long as they don't step out of line with their price...

Cheers!
David
 

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Been in racing a bit (cars) and have to agree with Marius on this.
The insides of a muffler might look the same between the two.
The higher price of genuine exhausts piping, as well as mufflers, lays in the research done to actually make that difference, not in sound, not in looks but in performance.
There were at least 4 tuning companies in the days that manufactured different exhaust manifolds for the little 1.6 Lancia Fulvia Coupe for different purposes.
Some made these for the hill climb races, some for circuit racing and others for a rally.
Companies such as TYGA make their money designing exhausts for two-stroke racing bikes, Sebring makes high quality and performance exhausts systems for four strokes.
I have yet to see any competitive racer use any of the cheap mufflers from any optical or noisy copy.
I guess these are not called copies for nothing, it's like a fake Rolex or pretty common in Asis Ölins.
At the end of the day no one needs any reasoning for running whatever on THEIR bikes as if this is what pleases them, all is (should be) good.


I didn’t think you would take me up on the offer. In other words, put your money where your mouth is. I can understand why you defend the higher priced genuine Akrapovic slip on, you bought one!!!

Do you really think there is any difference in performance gain between the higher priced name brand, than the cheap knockoff? There isn’t!!
Because all either one is, is a canister with fiberglass insulation inside that surrounds a perforated metal tube.

And stay on track Brother. I’m not comparing different motorbikes, just the different priced slip on mufflers.

Spend the money, enjoy the delusions!
 

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If you want cheap and noisy with no concern for power then just do as above and remove the baffle from the stock can. Or better yet, stubby the stock can. It works really well if all you care about is a louder pipe. Looks good too in my opinion and much cheaper than anything you’ll buy online.
 

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I watched one of the 44-teeth YouTube vids the other day, and they showed that inside a genuine aftermarket tailpipe the mesh inner pipe was spiralled to help increase the rate that the exhaust gasses were expelled.

It’s highly unlikely the “copy” systems will recreate the spiral format, and will most probably have a simple straight thru section. Obviously there’s no way to be sure without comparing the legit and copy systems side by side.

They did back to back dyno runs on an SRAD, the first run was with a loud ass aftermarket straight thru stubby exhaust, and the second run was with a legit (longer) Yoshimura exhaust. Result saw 4hp increase just swapping to the Yoshi exhaust.

There’s more development into exhaust systems than meet the eye.

But £500+ for an Akrapovic still hurts
 

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My tenpenny worth .....


I had a Gen 1 390 ....


Jerky as fruk - fitted a 42T rear sprocket then:



Went to the big main ktm dealers in BKK - Their mechanics are top of the pops for skill and knowledge - They cut open the under bike exhaust - took a few bits out and welded it back together, - To help it "breathe" better - and then re-mapped it......figures of a 5-6hp gain were quoted.....



Result was ok - Bit louder, but not bonkers loud and certainly pulled better - Total total cost was circa $80 usd ... money well spent i felt.....



When i got my Gen 2 390 - took it back to the same main dealer - and spoke to the mechanics...


Their advice / opion was that the Gen 2 is different to the Gen 1, in as much it can't be re-mapped - and bunging on a plug and play "piggy back" / after market system (original or snide) - was, in their opinion a "waste of money" as there were minimal power gains to be had (compared what they could do on the Gen 1 bikes) - plus would have higher fuel consumption ....


So from the horse's mouth ......


But it's your money ......if it makes you feel good spending $500 usd on a fuel box and another $500 on a swanky name zorst - by all means fill yer boots ......


1hp increase is 1hp after all ......


Me - 41T sprocket - standard exhaust / fueling and a $2 USD Ackrapovic sticker - and i'm as happy as a sand boy........
 

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