Modifying stock mufflers.
Banned
Joined: Oct 2007
Posts: 1,494
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RE: Modifying stock mufflers.
Looking at the stock mufflers it appears you can cut the weld at the outlet and knock out the baffle assembly. You can open upthe row of baffle holes to a larger size, you can also add more rows of holes to the baffle on each side of the baffle plug. Then pop the baffle assembly back in and tack weld it back in place. On another forum they call this "Gronking" the mufflers, this was a Sporty muffler mod, but the mufflers look like they are constructed the same way. I am going to get a set of take offs and try this in the near future, I like the stock look of the tapered mufflers. 08's are CATs (in CA.)(50 state?)so I am not sure if those can be modified? Tedious, but they actually sound pretty good and you can fool the exhaust police.
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CB
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CB
Cruiser
Joined: May 2008
Posts: 135
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From:
RE: Modifying stock mufflers.
ORIGINAL: cbz1200n
Looking at the stock mufflers it appears you can cut the weld at the outlet and knock out the baffle assembly. You can open upthe row of baffle holes to a larger size, you can also add more rows of holes to the baffle on each side of the baffle plug. Then pop the baffle assembly back in and tack weld it back in place. On another forum they call this "Gronking" the mufflers, this was a Sporty muffler mod, but the mufflers look like they are constructed the same way. I am going to get a set of take offs and try this in the near future, I like the stock look of the tapered mufflers. 08's are CATs (in CA.)(50 state?)so I am not sure if those can be modified? Tedious, but they actually sound pretty good and you can fool the exhaust police.
[sm=biker2.gif]
CB
Looking at the stock mufflers it appears you can cut the weld at the outlet and knock out the baffle assembly. You can open upthe row of baffle holes to a larger size, you can also add more rows of holes to the baffle on each side of the baffle plug. Then pop the baffle assembly back in and tack weld it back in place. On another forum they call this "Gronking" the mufflers, this was a Sporty muffler mod, but the mufflers look like they are constructed the same way. I am going to get a set of take offs and try this in the near future, I like the stock look of the tapered mufflers. 08's are CATs (in CA.)(50 state?)so I am not sure if those can be modified? Tedious, but they actually sound pretty good and you can fool the exhaust police.
[sm=biker2.gif]
CB
+1
Thats the only thing i did was to cut the plugs. Left everything else alone. Happy with how it sounds now. Feels alot better riding.
Cruiser
Joined: May 2008
Posts: 135
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From:
RE: Modifying stock mufflers.
I hope this works.....
This is a video i put together today on the sound i now have with the mod....
Exhaust Mod Ed's Custom
Its 11megs of quality video so give it a few minutes to download, depending on your connection of course....
This is a video i put together today on the sound i now have with the mod....
Exhaust Mod Ed's Custom
Its 11megs of quality video so give it a few minutes to download, depending on your connection of course....
Road Warrior
Joined: May 2009
Posts: 1,537
Likes: 4
From: The Great River Road, Wisconsin
I took a 3/4" steel rod and knocked the plugs out, and it made a considerable difference. Now it sounds like a Harley should. They have the dam* things so restricted out of the wrapper it ain't funny. It took all of 5 minutes to do, cost nahdah, and yet the baffles with wrap are in tact to absorb alot of the sound, and keep the factory look.
Now its just like glass packs on a P/U. When I get on it, it barks, and its mellow on decel.
Also, does anyone know of any shareware available to monitor the bikes vitals? I know I had found some for the Chevy OBC 1, and 2 once upon a time out on the web. Anyone know the protocol on the bikes (232,485,usb) comm port?
TIA,
Bob
Now its just like glass packs on a P/U. When I get on it, it barks, and its mellow on decel.
Also, does anyone know of any shareware available to monitor the bikes vitals? I know I had found some for the Chevy OBC 1, and 2 once upon a time out on the web. Anyone know the protocol on the bikes (232,485,usb) comm port?
TIA,
Bob
Last edited by VTL nut; Jun 2, 2009 at 03:38 PM.
6th Gear
Joined: May 2010
Posts: 10
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its an old thread but i needed to make posts. I just performed this mod on my stock 09 fat bob...i drilled a 3/8" hole in the plug off to the side and it made a huge difference...if at some point i want more sound, i will drill another 3/8" hole opposite of the last hole, should make it a bit louder...then when all else fails, i'll just drill out the plugs altogether...i'm cheap and this gives me basically three different exhausts...enough time to save cash for my rush slip ons and i like it so far!
Cruiser
Joined: Sep 2007
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From: Cleveland, Ohio (how do I put up with this place?)
I then went to a 1" square tube, its louder, and no popping on decel
Intermediate
Joined: May 2010
Posts: 32
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so can i punch a hole in my 2010 superglide mufflers?if so do i want to do it from the inside or from the outside? or do these have a cat thats in there and i cant do it? also- what about just taking the dam muffler off and running without it?not enough back pressure?
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Cruiser
Joined: Sep 2007
Posts: 183
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From: Cleveland, Ohio (how do I put up with this place?)
Get a 2-3' long piece of rebar our any other device you decide on.
One sledge hammer.
Insert from exhaust end of pipe and tap till it goes through.
STOP, there is no second baffle to punch!
You may need some pliers to twist the device for removal.
I am not responsible for the money you just saved.