Hi,
do you mean these? If yes, i can give you the feedback
I bought them few months ago and install them.
I must say that I was disappointed with the sound, because since they are homologated, the noise is defacto the same as the original. Friend of mine told me that they are maybe more silent than the originals.
As for the opening, it's not exactly a simple procedure and after some investigation I hesitated if I would not sell them and stay with the original.
But then i said let's give it a try....
The DB killer is in the shape of the Bmw logo and is very well welded into the tube using spot welds in 4 places. Of these, 2 points are inaccessible because they are hidden underneath the logo shaped lids. I tried to undo the first two visible welds, but the material is very hard.
It ended up destroying the logo, but even so I was not able to remove the Db killer because the remaining two welds were not within reach anyway. It was either not possible to get to them with a micro-cutter and a flexible extender.
I had to take off the decorative end caps, drill out about 10 welds around the circumference and carefully remove the bottom of the exhaust. Then I inserted a strong wire into the drilled holes and gradually pulled out the whole inside of the exhaust.
Then you need to take off the thermal wadding to get to the inner tube.
This tube however, is also welded to the bottom of the exhaust. With the first exhaust I managed to remove the tube and got to the welds of the Db killer. After drilling them I finally knocked out the killer with a piece of silon.
I couldn't do it with the second exhaust because the welder was bored probably and everything was welded with about a thousand welds. I have to found the places where the internal welds were, drilled holes against them and then drilled the inner welds out.
Then you have to put it all back together, which is the funniest part.....wrap the thermal wadding with aluminum strapping and reassemble the exhaust.
This was the hardest part, because after disassembly and reassembly, the volume of wadding grew and it was a problem to stuff everything back in. It took me almost five hours....
It is necessary to check the correct position of the inner part of the muffler and the cover, otherwise the decorative end caps will not be straight.
Eventually the two parts need to be put back together. Either weld them in place of the drilled holes, or like me, cut the edge and bend it inwards so that the inside doesn't fall out.
The first time I used the rivets, but I didn't realize that I couldn't fit a decorative cover because the heads exceeded the diameter.
So far I have chosen the cut and bend method so that I can open the exhaust again if necessary.
The sound has changed dramatically, it is beautifully deep and rumbling, but not annoying. Unfortunately there was no time to test it on the road due to the weather.
Was it worth it? I spent almost 3 days on it, defacto "destroyed" expensive branded exhausts and of course now they are not "street legal"...but they sounds good to me.
About the ''out of the box mufflers'' : they are very well made(yeah it's Akrapovic), personally I don't like the cover at the joint between the headers and the end cap, there is a big gap from above, the overall look on the motorcycle is decent and good.
I can add some pics and video with sound when i will be in garage.
Hope it can help you
