Dyna Glide Models Super Glide, Super Glide Sport, Super Glide Custom, Dyna Glide Convertible, Super Glide T-Sport, Dyna Glide Police, Dyna Switchback, Low Rider, Street Bob, Fat Bob and Wide Glide.
Sponsored by:
Sponsored by:

What I did to murder my stock exhaust.

Thread Tools
 
Search this Thread
 
Old Oct 22, 2010 | 12:14 PM
  #11  
Muff Daddy's Avatar
Muff Daddy
Advanced
Joined: Jun 2010
Posts: 73
Likes: 0
Default

Might have to try this to get me by until I buy my short shots.
 
Reply
Old Oct 22, 2010 | 12:18 PM
  #12  
SBRob's Avatar
SBRob
Seasoned HDF Member
Photogenic
Photoriffic
Shutterbug
Joined: Oct 2008
Posts: 7,641
Likes: 4,876
From: Missouri City,TX
Default

Entertaining post...
 
Reply
Old Oct 22, 2010 | 12:47 PM
  #13  
risdo's Avatar
risdo
Road Captain
Joined: Nov 2006
Posts: 609
Likes: 3
Default

That was great! Although, I gotta say, I bored mine out with a 1-1/4" hole saw, and they sounded like crap.

SBRob, what wheels are those?
 
Reply
Old Oct 22, 2010 | 01:15 PM
  #14  
dreamer65's Avatar
dreamer65
Road Warrior
Joined: Feb 2009
Posts: 1,648
Likes: 5
From: Willow Spring, NC
Default

what no video so we can hear them there pipes
 
Reply
Old Oct 22, 2010 | 01:45 PM
  #15  
pontiac69's Avatar
pontiac69
Outstanding HDF Member
Joined: Sep 2010
Posts: 2,357
Likes: 8
From: Pa
Default

Originally Posted by dreamer65
what no video so we can hear them there pipes

 
Reply
Old Oct 22, 2010 | 01:46 PM
  #16  
Black Bart's Avatar
Black Bart
Road Master
Joined: Aug 2006
Posts: 1,189
Likes: 3
From: Massachusetts
Default

Originally Posted by dreamer65
what no video so we can hear them there pipes
+1, We want to hear the results!
 
Reply
Old Oct 22, 2010 | 01:52 PM
  #17  
Mike T's Avatar
Mike T
Outstanding HDF Member
Joined: Aug 2010
Posts: 3,486
Likes: 6
From: Union,Ms
Default

Originally Posted by Ovaltine Jenkins
So I ride literally every day, and usually get up early enough that even chickens and bats have the good sense to still be sleeping. Given that I have quite a few neighbors, I don't want to be "that super-loud biker guy who scares children and quite possibly rapes elephants".

So I figured I'd modify the stock exhaust so that it's just loud enough to be heard by the rider at speed, but not loud enough to trigger a Homeland Security emergency mobilization.

I worked slowly. For any n00bs reading this thread, the stock slip-ons for the new Wide Glide (and, presumably, 2011+ Fat Bobs) basically are a 1 1/4" pipe with a plate blocking it about one foot in from the engine (front) end of the slip-on. Basically the gases stop at this plate, exit through holes in the sides of the tube, travel through the baffling material surrounding the center pipe, and then re-enter the center pipe on the other side of the blocking plate through more holes in the sides of the tube. From there they continue their merry way to the outlet end of the slip-on where, as legend has it, they go on to pillage towns and burn down nearby Smart cars.

It is this plate which blocks the tube that I modified. The catalytic converter is, in my case, in the header pipes just before the silencers, so that wasn't an issue. Here are my results:

Drilled four 3/16" holes through the plate - Very slight increase from "quiet" to "careless whisper".


Increased the holes to four 1/4" holes through the plate - Again, only a very slight increase in loudness. From "careless whisper" to "silence of the lambs."


Added two holes to bring it up to six 1/4" holes through the plate - Loudness was increased a bit more. From "silence of the lambs" to "Ready to Rumble".


Finally I said "f**k it" and went with the MOAB 1" hole saw. Drills are for sissies anyway. This gave a big improvement, with lots of low-end rumbling bass and no annoying high pitched "why don't you take out the garbage" BS. This increased the sound greatly, though not obnoxiously, all of the way up to "turn that hippie head-banging s**t off".


The maths:
Four 3/16" holes provide 0.11 square inches of unrestricted area for the gases to bypass the baffling.
Four 1/4" holes provide 0.20 square inches.
Six 1/4" holes provide 0.29 square inches.
Drilling the crap out of the plate with a 1" hole saw provides 0.79 square inches.
If the pipe were completely unrestricted, it would provide 1.23 square inches.

Keywords: FXDWG baffle plate exhaust slip-on drill WTF quiet loud old ladies elephants
 
Reply
Old Oct 22, 2010 | 03:05 PM
  #18  
SBRob's Avatar
SBRob
Seasoned HDF Member
Photogenic
Photoriffic
Shutterbug
Joined: Oct 2008
Posts: 7,641
Likes: 4,876
From: Missouri City,TX
Default

Originally Posted by risdo

SBRob, what wheels are those?
HD slotted six spoke textured black wheels.
 
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-1

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-2

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-3

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-4

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
story-5

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-6

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-7

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-8

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
story-9

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

 Verdad Gallardo
Old Oct 22, 2010 | 03:23 PM
  #19  
risdo's Avatar
risdo
Road Captain
Joined: Nov 2006
Posts: 609
Likes: 3
Default

Originally Posted by SBRob
HD slotted six spoke textured black wheels.
Thanks!
 
Reply
Old Oct 22, 2010 | 04:43 PM
  #20  
bikerlaw's Avatar
bikerlaw
Ultimate HDF Member
Joined: Jun 2007
Posts: 9,193
Likes: 494
From: Richmond, VA
Default

We need more posts like this one.
 
Reply



All times are GMT -5. The time now is 04:45 PM.

story-0
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-1
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-2
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-3
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-4
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-5
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-6
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-7
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-8
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE
story-9
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

Slideshow: Graeme Billington's left-hand-drive Shovelhead is as much about problem-solving as it is about classic Harley form.

By Verdad Gallardo | 2025-12-30 11:27:08


VIEW MORE