big city thunder baffles
Grand HDF Member
Joined: Jun 2009
Posts: 3,520
Likes: 270
From: Wellsboro, PA
I guess I didn't know you could use 'em in stock pipes. I suppose you can if they fit tight. I've had them & liked them, but used them in after-market full-system pipes on a couple of Yamahas that I had, before I got a Harley. I'd go to bigcitythunder.com, get the phone number & talk to this guy Jim, who might be the one answering the phone. He's the guy that'll answer your question. (unless somebody her has used them in stock pipes.)
Intermediate
Joined: Jun 2009
Posts: 35
Likes: 0
From: Portland Oregon
Big City Thunder Baffles
If you are using them on a stock system you have to core out the baffles in your stock mufflers in order to use them. Call them up they are very helpful and knowledgable. I have the monster baffles and really like them. Look on You Tube there are sound clips available.
They definitely know their stuff. I called and spoke with a woman who explained everything and answered all my questions. Core those stock pipes and put some in. I am interested in hearing how this will work.
Cruiser
Joined: Jan 2008
Posts: 223
Likes: 0
From: texas
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Road Master
Joined: Jun 2006
Posts: 812
Likes: 0
From: Jaw-Jaw (Near The BIG Chicken!)
Tried them on a '06 Fat Boy and a '06 Night Train at different times. Bottom line, all they have going for them is noise... LOUD NOISE. My son had to have his bike dyno'd again and still lost a good bit of power. He put his SE slip ons back on and got another dyno. If you take a look inside of them, they look like straight pipes, except for what I believe was a flame arrestor. If you don't mind LOUD and losing torque & hp, go for it.
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Tourer
Joined: Oct 2007
Posts: 392
Likes: 2
From: Southeastern Wisconsin
Did them on my sons 2009 Fat Bob a few weeks ago. They are Loud with any application of throttle!
Drilled out the three rivets on each stcok muffler to remove the baffles. Pounded the baffles out using a pipe, drilled a hole in each stcok pipe for the set screw to hold in the thundermonster baffles. Whole thing took about an hour, and another hour to get the tools out, jack the bike up in the air, and put everything away when done.
Drilled out the three rivets on each stcok muffler to remove the baffles. Pounded the baffles out using a pipe, drilled a hole in each stcok pipe for the set screw to hold in the thundermonster baffles. Whole thing took about an hour, and another hour to get the tools out, jack the bike up in the air, and put everything away when done.
Cruiser
Joined: Jan 2008
Posts: 223
Likes: 0
From: texas
Did them on my sons 2009 Fat Bob a few weeks ago. They are Loud with any application of throttle!
Drilled out the three rivets on each stcok muffler to remove the baffles. Pounded the baffles out using a pipe, drilled a hole in each stcok pipe for the set screw to hold in the thundermonster baffles. Whole thing took about an hour, and another hour to get the tools out, jack the bike up in the air, and put everything away when done.
Drilled out the three rivets on each stcok muffler to remove the baffles. Pounded the baffles out using a pipe, drilled a hole in each stcok pipe for the set screw to hold in the thundermonster baffles. Whole thing took about an hour, and another hour to get the tools out, jack the bike up in the air, and put everything away when done.