Stock muffler mod Part 1 - GL1800Riders
 
LinkBack Thread Tools
post #1 of 9 (permalink) Old 11-13-2014, 11:11 PM Thread Starter
Contributing Member
 
troaf76's Avatar
 
Join Date: May 2010
Location: Chaffee, Missouri
Posts: 51
Garage
Stock muffler mod Part 1

It may be here already, but I sure as heck can't find a thread detailing a stock muffler mod. So, here is one. To start it off, here's is a fairly accurate drawing of the inside of a stock unit. All measurements are approximate, but they are pretty close to real life. The exhaust comes in the front (left in pic). It goes into the 1 1/2" pipe at the top of the pic. Some of the sound goes into the perforated area of this pipe and directly into the center chamber. From there, this exhaust has a straight shot out the small exit pipe at the rear. The rest of what doesn't enter the center chamber has no where else to go but into third chamber and out through the perfs in the exit pipe.

Click image for larger version

Name:	muffler guts.jpg
Views:	564
Size:	24.8 KB
ID:	62401

I wanted the pipes to still look like stock afterwards. Using a cutoff wheel and dremel tool, I cut the straps that hold the chrome covers on. There are six straps on each muffler. NOTE: on my '08 the center set of straps weren't connected to the covers, so I didn't have to cut those straps. I marked the strap locations to make sure and get the chrome back where it goes later. Here's a closeup of one of the cuts.

Click image for larger version

Name:	reassembly marks1 (800x450).jpg
Views:	618
Size:	43.0 KB
ID:	62402

Now the point of no return. I cut them in two 7 1/4" back from the factory weld near the front. And then again 4 1/2" back from there. I made two cuts so I could try different things in there to get the type of sound I wanted. Here's the pics of the cuts and results.

Click image for larger version

Name:	first cut (800x450).jpg
Views:	562
Size:	50.5 KB
ID:	62403

Click image for larger version

Name:	mark second cut (800x450).jpg
Views:	578
Size:	66.4 KB
ID:	62404

Click image for larger version

Name:	ready for welding (800x450).jpg
Views:	639
Size:	54.5 KB
ID:	62405



'08 Caliente Red GL
'85 Red Yamaha Maxim 700
'79 Black Yamaha 500
'79 Black Honda 750K
'76 Gold Triumph 750 Bonnie
'74 Blue Yamaha 500
'71 Metallic Green Honda CL 350
troaf76 is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 11-13-2014, 11:47 PM Thread Starter
Contributing Member
 
troaf76's Avatar
 
Join Date: May 2010
Location: Chaffee, Missouri
Posts: 51
Garage
Stock muffler mod Part 2

Okay, inside the front piece there's a solid baffle plate. This plate will be just forward of the 7 1/4" cut. The only hole in it is where the "center" pipe comes through. This shot is the front piece after I jigsawed the baffle plate out. (This one is the right muffler. It is formed this way for clearance around the bike's final drive. The left one has the same guts, but is perfectly round.)



I stopped here with the mod and duct taped everything back together to check sound. The exhaust, or at least part of it, now had a straight shot out the exit pipe. I really thought it would make quite a difference, but it didn't. Still wanting to take baby steps, the next thing I did was weld the front of the "center" pipe shut. This would force the exhaust out the exit pipe instead of letting some of it enter the rear chamber. Here's my weld location. (Please don't laugh at my welding. It doesn't leak and who cares what it "looks" like.)



Back together again for a test. The cap did its job. It gives a nice mellow note at idle, and gradually gets louder as the revs heat up. It's just about the sound I was expecting and hoping for. After welding it all back together and doing a little bit of mounting bracket tweeking, you can't tell they're not totally stock by looking at them.

As an aside, the material these pipes are made of is NOT friendly to work with. It doesn't look like stainless or something exotic to me, but it is hard to cut and harder to weld. I used a regular sawzall with a 9" metal blade to slice it up. Also used standard metal jigsaw blades where needed. The hardest part about cutting them was finding a way to hold them and not destroy the roundness. I ended up using some 12" wooden clamps in conjunction with a solid table.

Most of the inside of the mufflers is lined with an insulation-looking stuff held in place by a perforated liner. You can kinda see what it looks like in the last picture above. I paid no attention to it for the most part, and just put it back where it was when it was time to reassemble things.

About welding. I run a 110 volt Lincoln wire feed welder. It uses .035 flux core wire. I had a ton of trouble with burnthrough. I ended up cutting 1" wide strips of 18 gauge and using it as a backer to the welds. This worked much better. The real trick, I think, is to take your time. I measured everything 3 or 4 times before tacking each weld together. Then used short beads at different spots around the muffler to finish up.

There are a few other pics of this mod in one of my albums in my profile. Make yourself at home. I can come up with a shot or two of the finished product if someone wants to see that as well. Just let me know. At this time I don't have a way to record the sound they make. A go-pro is on my Christmas list, so maybe after the holidays I'll be able to put one on here. Suffice it to say that I'm satisfied with the sound. My bike still has the cats on it, so it's by no means "dual" exhaust.



'08 Caliente Red GL
'85 Red Yamaha Maxim 700
'79 Black Yamaha 500
'79 Black Honda 750K
'76 Gold Triumph 750 Bonnie
'74 Blue Yamaha 500
'71 Metallic Green Honda CL 350
troaf76 is offline  
post #3 of 9 (permalink) Old 11-14-2014, 07:35 PM
Seasoned Member
 
Waldo's Avatar
 
Join Date: Aug 2005
Location: NE Ohio
Posts: 7,446
Quote:
Originally Posted by troaf76 View Post
. At this time I don't have a way to record the sound they make. A go-pro is on my Christmas list, so maybe after the holidays I'll be able to put one on here. Suffice it to say that I'm satisfied with the sound. My bike still has the cats on it, so it's by no means "dual" exhaust.
What did you take the photos with? If you have a smart phone or that camera which should take video of any kind, you can take a short video which will have the sound on it. Open a you tube account if you don't already have one and click the film strip to point you your video. To wit: this video of mainly the sound of a dying ADG. If you can't do that, pm me and I will give you an e-mail to send the video to and I will take care of getting up here for you.

Click image for larger version

Name:	Image1.jpg
Views:	1210
Size:	45.2 KB
ID:	62422

[video=youtube;gZEM5NzxaRA]https://www.youtube.com/watch?v=gZEM5NzxaRA[/video]



'06 Chrome on Black on Black
#notmypresident
Waldo is offline  
 
post #4 of 9 (permalink) Old 11-17-2014, 01:25 PM Thread Starter
Contributing Member
 
troaf76's Avatar
 
Join Date: May 2010
Location: Chaffee, Missouri
Posts: 51
Garage
Muffler mod

I may just try the phone, Waldo. I did shoot a sound bit and played it back on the phone. It sounded pretty much useless through the phone. I take it the sound will be better if put on a computer/or youtube. We are in the deep freeze here in southeast Mo right now. It's got to warm up before I do anything much outside. Stay tuned.
Don



'08 Caliente Red GL
'85 Red Yamaha Maxim 700
'79 Black Yamaha 500
'79 Black Honda 750K
'76 Gold Triumph 750 Bonnie
'74 Blue Yamaha 500
'71 Metallic Green Honda CL 350
troaf76 is offline  
post #5 of 9 (permalink) Old 12-08-2014, 05:21 PM
Seasoned Member
 
mopar's Avatar
 
Join Date: Oct 2004
Location: Anderson, South Carolina
Posts: 217
If I followed this correctly, you ended up with a stock muffler with the front partition removed and the entrance to the third chamber welded up. Could you obtain the same results by making one cut at 63/4" back, removing the partition and welding up the tube at that location? I realize the tube perforations would allow some exhaust into the third chamber. I am assuming the center tube was removed between your cuts. Is the tube round on both mufflers? Could you drive a steel Dorman plug down the tube to the other end?


Dennis
Anderson SC
2014 Level 3
Blacked out Blue
DS#1681



mopar is offline  
post #6 of 9 (permalink) Old 12-09-2014, 09:33 AM
Seasoned Member
 
ChrisE's Avatar
 
Join Date: Aug 2010
Location: Lebanon, TN
Posts: 3,452
If a more rasp'y sound is what you are after, an an alternative method, BigCat achieved this by just drilling a couple of extra holes in the end plate of the exhaust.

My Toys (Current Stable)
'15 Ducati 1299 Panigale S
'15 Ducati Multistrada
'12 Aprilia Tuono V4 APRC
'08 GL1800 (Level 3) Traxxion Full Monty, '04 Uni-Go Trailer (Sold)
'07 Suzuki GSXR1000
'08 KTM 300XCW
'07 Ducati 1098S
'98 Yamaha R1
'93 Bimota DB2
'75 Honda CB400F
DS #1166 (Once)
ChrisE is offline  
post #7 of 9 (permalink) Old 12-12-2014, 12:47 AM Thread Starter
Contributing Member
 
troaf76's Avatar
 
Join Date: May 2010
Location: Chaffee, Missouri
Posts: 51
Garage
Mopar,
You might could try it that way. I didn't do that exact combination. I was kinda learning as I went is the main reason I cut mine twice. The larger pipe that "connects" the front chamber to the third one is in essence gone. It is cut off even with my second cut, so that's where I put the cap on it. I'd say go for it and see what it sounds like. You could always drill that cap/plug back out if it didn't make it any louder. And yes, both mufflers are the same inside(all interior tubes are round). The only difference is the outer shell on the right muffler to accommodate the bike's final drive unit.
Don



'08 Caliente Red GL
'85 Red Yamaha Maxim 700
'79 Black Yamaha 500
'79 Black Honda 750K
'76 Gold Triumph 750 Bonnie
'74 Blue Yamaha 500
'71 Metallic Green Honda CL 350
troaf76 is offline  
post #8 of 9 (permalink) Old 06-04-2016, 06:01 AM
Seasoned Member
 
100MPG's Avatar
 
Join Date: Sep 2009
Location: Long Island NY
Posts: 1,984
Sorry for dragging this back to life. I have an extra set of pipes to attempt this. I am looking for a little bit more tone. Did you ever get the video/sound file?
100MPG is offline  
post #9 of 9 (permalink) Old 09-04-2016, 11:21 PM
HPJ
Seasoned Member
 
Join Date: Feb 2016
Location: Houston, Texas
Posts: 211
I would love to hear this! Please post a link to a video file or sound file. Thank You!
HPJ is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the GL1800Riders forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome