Modified muffler core job - nice!

[sejman]

I had some extra time this weekend and have been itching to get some more rumble out of my stock cans.  I searched everything looking for some good instructions, but eventually decided to try the method outlined on the Ducati Suite site, which he claims can be done without even removing the cans from the bike.  I mustered up my courage and went at thinking that worst case, I'll have an excuse to buy some nice "real" slip-ons.

The method explained on the Ducati Suite is involves cutting out the ring around the small pipe exit on the endcap (which is simply cosmetic), and then continue cutting/grinding away and pulling out everything you can get at back to about 3" (or as far back as you can go).  Easier said than done.  Here's all you really need to do:

Drill 2 or 3 holes very close to each other in the stainless steel  ring around the small exit pipe.  Punch out a slot with a large screw driver.  Now insert Jigsaw blade (metal cutting blade for thin sheet metal) into slot and cut out as much of this sheet metal as you can.  I used a block of wood between the bottom of the jigsaw and the end cap to prevent scratching the larger exit ring and to keep the blade from bottoming out on the inner guts.   Use a grinder (all I had was a Dremel, but it's good enough for what's left over) to clean up the sharp left over edges.  Now you have a clear view of the actual rear wall of the muffler, but it's about 2" back there.

Next I just drilled a ring of small holes (maybe 3/16")  in the rear wall of the muffler completely around the actual exit pipe and then used a large screwdriver to punch out th remaining sheet metal between all the holes.  This leaves an exit ring around the existing small diameter pipe from the rear most chamber (chamber 3).  This all sounds pretty hacked, but the result looks better than it may sound (it's pretty dark back there).  There is no need to try and remove any packing (I didn't run across any) and there is no need to try and remove the small diameter exit pipe.  From what I can tell, this is just a whole lot of work is useless.  The main thing is to allow the exhaust to escape the last chamber directly to the outside, and that small diameter exit pipe looks nice when exposed inside the opened up end cap.

The actual sound is amazing - I'm sure it's basically the same as all the other similar options.  Much louder.  Much deeper.  This exit ring around the inner pipe allows all the exhaust that would normally have been routed back to the second chamber straight out the back.  The area of the newly formed direct exit is approximately the same as the old exit pipe (about 0.8 sq.in. figuring about 1/4" of slot around the old pipe) so it's doubled the output area of the total muffler system (not that I'm expecting any real performance improvement).

The first can took me a good couple of hours to figure all this out, including a trip to home depot to buy some better drill bits and the right jig saw blades.  The second can took me less than a half hour.  I still have some finish grinding work to make the end caps look clean (where I couldn't get the jig saw right up to the large outer stainless opening) but this will be quick.  I'll post some pictures (and maybe audio) when I get a chance.

[teddy037.2]

which cans are these for? DSS? or S*R?

[sejman]

These are the stock low-mount cans for the M900 (I think M750 are the same). 

I honestly don't know how anyone gets the aluminum sleeves off of these things without tearing them up.  While working on the first side I temporarily removed the whole muffler from the bike to see if it would be easier to work on and even tried to push the sleeve down using a variety of techniques (just to see if it would make the whole job easier).  Forget it.  My sleeves are on so tight and the aluminum is so soft that there is just about no way to get them to budge unless you had some sort of rubber coated metal band that you could tighten over the sleeve and then whack that somehow.

Anyway - all that was a waste of time.  Leaving them on the bike while doing the work was far easier.

[He Man]

These are the stock low-mount cans for the M900 (I think M750 are the same). 

I honestly don't know how anyone gets the aluminum sleeves off of these things without tearing them up.  While working on the first side I temporarily removed the whole muffler from the bike to see if it would be easier to work on and even tried to push the sleeve down using a variety of techniques (just to see if it would make the whole job easier).  Forget it.  My sleeves are on so tight and the aluminum is so soft that there is just about no way to get them to budge unless you had some sort of rubber coated metal band that you could tighten over the sleeve and then whack that somehow.

Anyway - all that was a waste of time.  Leaving them on the bike while doing the work was far easier.

really? i just grabed the aluminum sleeve and hammered the inner muffler and it popped out with 1 wack.

[sejman]

Here's are some quick pics before cleaning up and painting the inside flat black:

[DucLeone]

just use a dremel and a bunch of cutoff wheels,and cut the inner pipe from the inside
be alot cleaner

just my .02

when i did mine
http://www.hoosierhooligans.org/forum/index.php?topic=1099.0

[sejman]

I actually attempted that a few times on the first side, but gave up after going through 4 or 5 cutting disks.  Just for kicks I started it up like it was - wholly crap!  What a difference just the opened up ring made and just the one pipe!  I decided to leave well enough alone - finished the second pipe and to me it's perfect.  I agree that it could look cleaner (I've since painted the inside flat black which looks great) but I kind of like the "pipe within a pipe" look and I'm concerned about how much louder it will be with those inner pipes (and the remaining section of wall that would come with it) removed.

At some point I'll probably get some stock cans and chop them down more completely - I'd really like them to be about 3" shorter.

[sejman]

Took the bike to work today for the first real ride with these modified cans - WOW.  Much louder, but a nice low, mellow, and sweet sound.  Never raspy or metallic.  Now I finally understand what people are talking about when they reference the unique sound of a Ducati.  I went from really liking this bike to loving it.  Riding it is now the complete experience - it's like a whole sense was missing.

That's it.  I'm now in love.