Modifying Mufflers
Road Captain
Joined: May 2008
Posts: 616
Likes: 70
can I make a suggestion to anyone considering doing this? buy a bit extension long enough to reach each tab from either end of the mffler and a hole saw (forgot the size but you can figure that out) to drill out the tabs instead of pounding on your pipes with hammers, etc. much easier and the screw up factor is virtually eliminated. I've done this to all my harleys. it's a cheap and easy way to get a good sounding bike.
let me know if you have any questions.
let me know if you have any questions.
Tourer
Joined: Dec 2005
Posts: 251
Likes: 2
From: Upstate, NY
Did you lose any low end torque? I picked up a bike a while back that had factory mufflers cored by the dealer. Low end torque was awful. Put a set of SE mufflers on, nothing else, and the bike ran great.
Road Captain
Joined: May 2008
Posts: 616
Likes: 70
nothing that was noticable without a dyno.
Road Master
Joined: Oct 2008
Posts: 1,086
Likes: 1
From: North Carolina
I did the 2in. pipe inside of the gutted stock muffler and it sounded great compared to stock!!
(for about a week
) Then I noticed that it still has that "poppy" sound, kinda like the air is havin a hard time gettin out, just like the stock muffs. Ohhh for some Thundercones......
(for about a week) Then I noticed that it still has that "poppy" sound, kinda like the air is havin a hard time gettin out, just like the stock muffs. Ohhh for some Thundercones......
Elite HDF Member
Joined: Dec 2007
Posts: 4,271
Likes: 29
From: Green Country,Oklahoma
I put a 1/2" hole in each baffle of my stock N mufflers,they sound pretty good,look stock,I guess it runs pretty good as it whips everyones 96 inchers and the OHP says it runs 110 mph!
Intermediate
Joined: Apr 2007
Posts: 27
Likes: 0
From:
Smooth Bore Mufflers
I purchased these off Ebay about 2 years ago, and have been pleased with them. It appears that they took a hole saw and cut out the solid baffle out and left the inside pipe. The guy told me that if I wanted to make them louder, to drill some additional holes in the second baffle. I did add 2 holes and it seemed that it opened it up. I haven't looked into the front end of the mufflers to see if there were any mods. I will try to post some pics from the rear if anyone wants to see them. Hope the video works.
Stage I
Joined: May 2009
Posts: 1
Likes: 0
From: Broken Arrow, Oklahoma
Would like a little more info if anyone can help
I bought a 2005 RK. This is my first bike so learning as I go so excuse me if I sound a little stupid. I have read all the forums about the drilling. With the purchase of the bike, just cant afford $500 for the Rineharts just yet. I drilled out the rear baffle and left the inside pipe. It did get a little louder, but not loud enough. I pulled the muffler off and on the inlet end, it looks like honey combed material. Is this the packing? If so, what can I do to it. I am afraid of doing anything drastic without getting a little advise. Thanks for any help you can give.
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Road Master
Joined: Feb 2006
Posts: 897
Likes: 0
From: South-Central Minnesota
I did my stock mufflers the same way pretty much. I stuck a piece of bar stock in the back end of the muffler and beat on it with a bfh until in pops through the first plug. Keep on pushing and it will hit the next plug. Start beating again and you will pop through that one too. Now go back and dress them up by knocking the edges down.
Advanced
Joined: Aug 2008
Posts: 74
Likes: 0
I'm not clear on this. Did you take the muffler off and drill out the inlet side, or the exhaust side? Because I thought the inlet side had the cat-converter in it.
About drilling all the way through. Not sure if it is the same on HD's, but when I was into sport bikes we would only drill out one baffle. If we drilled all the way through, the bike sounded funny, lost torque, and in general did not run that great. Removing one baffle keeps some back preassure, and seemed to give us the best results short of going aftermarket.
About drilling all the way through. Not sure if it is the same on HD's, but when I was into sport bikes we would only drill out one baffle. If we drilled all the way through, the bike sounded funny, lost torque, and in general did not run that great. Removing one baffle keeps some back preassure, and seemed to give us the best results short of going aftermarket.