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Discussion Starter · #1 ·
I'm not sure if this makes me a big old hypocrite, but today, despite all my claims that I like a quiet bike, I removed the db killer in my Akra slip-on. Why? When I was at the KTM dealership on Thursday, I heard what this setup sounded like, and it tickled my fancy. Now, that I've done it, I'll see if I like living with a bike that is louder than it was, but I'm sure I'll love it at the track day tomorrow.

Here's what I used:
4570

Not pictured is my drill (corded, high-speed).

Using a 3/16"bit, I drilled out all of the rivets holding in the carbon end cap. Rapid Tap oil makes the job much easier. The punch was used to tap down the center of the rivet if it prevented the bit from getting all the way through the rivet top. I also had to tap a couple of rivets into the canister to get the end cap to slide off. Once all the rivets were done, the end cap slid right off with minimal effort.

Using an 8mm socket and a breaker bar, I removed the bolt securing the db killer into the end cap. Next, I took the narrow vise grip and clipped it to the db killer. Then I clamped the bigger vise grip to the smaller one at a right angle, giving me something to tap with the hammer. The db killer didn't come out. Instead, the whole end cap did. After that, I just tapped out the db killer from the inside of the end cap. This way I didn't damage the db killer in case I want to put it back in the muffler.

4571


Sliding the titanium end cap back in place was easy, but it did take some light tapping with the hammer to get the rivet holes to line up. Then I just slipped the carbon fiber end cap on and re-riveted everything. Because I'm not sure I'm gonna keep this setup, I used cheap, easy-to-remove aluminum rivets. I've ordered Akra ones from Revzilla, and I'll either put the db killer back in place or clean up the rivets with the shiny stainless ones once I'm certain that I like the additional noise.

4572


I can't wait to hear it at full song at Buttonwillow tomorrow!

4573
 

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Discussion Starter · #4 ·
Funny, I felt guilty for not including more photos. I guess I can’t get away from the office.
 

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Having to remove the end cap is a bit weird.
But the reason is Euro4 onwards.
In theory the dB killer is "not easily removeable".

It is to avoid any "But officer, it was there when I left home".

Other mfrs have found other ways around the ruling.
 

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I used the same method. Wished I'd had some of that Rapid Tap oil, because drilling out those stainless steel rivets was a p.i.t.a. I'm happy overall, though - it's louder than stock, but not too much, imo. I don't find it obnoxious.
 

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I'm not sure if this makes me a big old hypocrite, but today, despite all my claims that I like a quiet bike, I removed the db killer in my Akra slip-on. Why? When I was at the KTM dealership on Thursday, I heard what this setup sounded like, and it tickled my fancy. Now, that I've done it, I'll see if I like living with a bike that is louder than it was, but I'm sure I'll love it at the track day tomorrow.

Here's what I used:
View attachment 4570
Not pictured is my drill (corded, high-speed).

Using a 3/16"bit, I drilled out all of the rivets holding in the carbon end cap. Rapid Tap oil makes the job much easier. The punch was used to tap down the center of the rivet if it prevented the bit from getting all the way through the rivet top. I also had to tap a couple of rivets into the canister to get the end cap to slide off. Once all the rivets were done, the end cap slid right off with minimal effort.

Using an 8mm socket and a breaker bar, I removed the bolt securing the db killer into the end cap. Next, I took the narrow vise grip and clipped it to the db killer. Then I clamped the bigger vise grip to the smaller one at a right angle, giving me something to tap with the hammer. The db killer didn't come out. Instead, the whole end cap did. After that, I just tapped out the db killer from the inside of the end cap. This way I didn't damage the db killer in case I want to put it back in the muffler.

View attachment 4571

Sliding the titanium end cap back in place was easy, but it did take some light tapping with the hammer to get the rivet holes to line up. Then I just slipped the carbon fiber end cap on and re-riveted everything. Because I'm not sure I'm gonna keep this setup, I used cheap, easy-to-remove aluminum rivets. I've ordered Akra ones from Revzilla, and I'll either put the db killer back in place or clean up the rivets with the shiny stainless ones once I'm certain that I like the additional noise.

View attachment 4572

I can't wait to hear it at full song at Buttonwillow tomorrow!

View attachment 4573
What's the verdict to loud? I'm debating removing mine! Power feel any different? Hopefully not less?
 

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Discussion Starter · #9 ·
What's the verdict to loud? I'm debating removing mine! Power feel any different? Hopefully not less?
I love the sound at the track and in the canyons, but I’m still on the fence about around town. However, I’m leaning towards keeping it. The power feels just about the same. I suspect that there may be a little more poop up top, but that’s not my primary emphasis. I definitely haven’t lost anything in the middle, but I don’t think that it gained anything either. We’ll see what happens when I get that custom map done.

There’s not much to the internal end cap. You could tap it, but it’d be super easy to strip.
 

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Finally somebody who does it properly, instead of drilling a hole in the carbon! I thought I was the only guy who thinks it needed to be done like this. Well done!
 
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