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Have any forum members performed the Akra Ti db killer mod (shortening)? Looking to get a bit more exhaust note with the db killer in. The exhaust without the baffle is just too loud (and too low) for my ears. Also, do any members that ride unbaffled, have a db killer they're willing to sell at a reasonable price? Thanks!
 

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Nakaji... shortening the inside part of the T1 baffle ruins the design and backpressure of the Akra T1 system. Hard to explain here but the Akra has three internal chambers. Exhaust gas enters chamber one and passes OVER AND AROUND the outside of those three small exit outlets inside the muffler. From there the exhaust gas enters chamber two ...does a U turn and enter chamber three...which exits out through the three small outlets.

If you shorten the inside of the baffle...exhaust gas goes direct from chamber one to the three small outlet pipes and out. Yes that makes the pipe louder but the backpressure and pipe tuning is lost....meaning it would never run the way Akrapovic designed it to.....and no amount of re mapping would fix it.

The "sound" you hear from your Akra T1 comes from the inside diameter size of those three small exit tubes. Enlarging the inside diameter of all three exit tubes would allow more "sound"....and still allow the Akra T1 to function the way it was designed to work with nearly the same backpressure. Unfortunately....removing all three exit tubes from that baffle and exchanging them for slightly larger inside diameter tubes is expensive and labor intensive. I know because I have done it on my FZ 07.

The FZ 07 has only TWO exit tubes on the Akra T1 baffle. They are 20mm inside diameter and restricted down to 19mm inside diameter at the center. I removed the 20mm tubes and installed slightly larger ones. The TIG welding took two hours to do. Now I have a nice deep sound while retaining the function of the Akra design. It took a month to accomplish and I'm not about to do it again....or make any for sale. It would be very expensive.

The only correct and cost effective way to make your Akra T1 a little louder would be to shorten all three OUTSIDE outlet pipes with a hacksaw by ONE INCH each. A flat straight cut will provide more "sound" than three SLASH CUT outlets. It won't be that much louder than it was..but it is the only option.
 
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I shortened mine cut it off just past the first welded piece removed about 1 1/8 inch just just right not to quiet not to loud didn't notice any seat of pants performance drop...
 

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Hello CD599,

Don't you think that Akrapovic did design the Akra T1 to run with or without the db killer ?
The 3 chambers are their to reduce noise but if you just remove the db killer, you also have exhaust gas going direct from chamber one to exit and this make no issue even if backpressure and pipe tuning is lost.

I even think that gain of HP are measured by Akrapovic without Cata and without DB killer.
So cutting the DB killer to reduce noise and have gas going direct does not seem to be an issue, right ?

Thanks
 

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Hello CD599,

Don't you think that Akrapovic did design the Akra T1 to run with or without the db killer ?
The 3 chambers are their to reduce noise but if you just remove the db killer, you also have exhaust gas going direct from chamber one to exit and this make no issue even if backpressure and pipe tuning is lost.

I even think that gain of HP are measured by Akrapovic without Cata and without DB killer.
So cutting the DB killer to reduce noise and have gas going direct does not seem to be an issue, right ?

Thanks
Wrong. The "issue" would be fuel mapping. Fuel mapping would be wrong without the baffle and you would lose horsepower...not gain any.
 
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Its a bit hard to tell in this picture but i took a hacksaw to the DB killer and sawed all three "pipes" that stuck out of it. In my opinion the pipes sticking out made the exhaust look a little distracting. I liked the clean look of the exhaust without the killer in but I didnt want to sacrifice the design of the exhaust with the killer. That steel is very thick and it took hours to get through all of them carefully by hand so there was no damage done to the rest of the exhaust. I personally love the finished product. Just adding this in here to give you an idea of whats possible. Cheers.
 

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Hey just wondering if you have done a noise test with the "improved" DB killer in? I just got a nosiy bike ticket today, my Ti akra doesnt have the Db killer in it. Basically the officer showed me that I failed the test at idle. I was at 96Db at idle without the baffle. I needed to be at 92Db. But I love how "loud bikes save lives" so I want something in between. Have you tested it?
 

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OP, don't listen to the naysayers. Of course you have searched the Forum for "Akra Ti DB Killer Mod". Thee is no problem to modify. First I cut 2 inches off the inside tubes, and it was still to quiet. Then I cut the outside tubes to flush with the rim of the can. Perfect sound, killer performance! I do have an ECU reflash. But look at my post "Akra Ti DB Killer Mod", lots of conversation there on the subject
 
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