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Mar 1, 2012 | 04:06 PM

#11

JohnC FXDX

Road Master

Joined: Jul 2011

Posts: 1,016

Likes: 3

From: West New york, NJ

Quote:

Originally Posted by Shredding rubber

Good place to start. I suggest a dyno tune. Remote tuning is fine if every motor was the same and we all lived at the same elevation but we don't. A dyno tune is custom,so any little difference or variation can be tuned for on the spot.
Amd from what I have read the thunderheader costs a bit of torque on the bottom end. Perhaps a dyno tune can help you there.

I've never heard of the thunderheader costing torque at the low end, but they do have a torque dip problem. There is an easy fix for it. Go to YouTube and search for thunderheader mod or fix. It has to do with bending the inside baffle to be tighter to the outer pipe. It is done through the end if the tailpipe.

Mar 1, 2012 | 07:28 PM

#12

Mike650

Road Captain

Joined: Jan 2012

Posts: 710

Likes: 2

From: San Bruno

that fix was also for a carburated bike. a fuel injected bike might not have that problem. and if you wanna pound on your $700 pipe go ahead. im fine with mine the way it is.

Mar 2, 2012 | 06:49 AM

#13

8541hog

Ultimate HDF Member

Joined: May 2008

Posts: 6,642

Likes: 48

From: Ogden, UT

Two things besides tune that will cause decel pop.

First, has been mentioned, loose/leaking exhaust flange at the head.

Second, how you roll off the throttle, if you do not roll all the way off, ie when shifting, you will get decel pop.

Mar 2, 2012 | 08:13 AM

#14

JohnC FXDX

Road Master

Joined: Jul 2011

Posts: 1,016

Likes: 3

From: West New york, NJ

Quote:

Originally Posted by Mike650

that fix was also for a carburated bike. a fuel injected bike might not have that problem. and if you wanna pound on your $700 pipe go ahead. im fine with mine the way it is.

Who doesn't like pounding there pipe?

I guess that makes sense a little because the FI can adjust. I thought it had to do with a little more restriction to create the right back pressure. If it is a pipe issue, the FI still won't correct it 100% though. It is more of a simple bending of the internal baffle than really a pounding.

Mar 3, 2012 | 09:30 PM

#15

crimson13

Thread Starter

Grand HDF Member

Joined: Sep 2011

Posts: 4,080

Likes: 61

From: Leroy,Alabama

thanks yall for all the suggestions i checked exhaust flanges twice and I guess I did not check good enough the front flange nut was loose I missed it, I got it torqured and tight now so far so good thanks again

Mar 3, 2012 | 10:07 PM

#16

fxdb10

Advanced

Joined: Apr 2011

Posts: 93

Likes: 1

From: CA

I have the same thing going on with my bob. Nothing to worry about, the PCV that came from fuelmoto is close but not perfect. A little on the rich side. Still runs better then the dealer download in my opinion. Just wait till you do some real engine mods before you dish out for a tune, save yourself some money. I like the occasional pop on decel its like a little treat once in awhile IMO.

Mar 4, 2012 | 03:13 AM

#17

Patsplace

Cruiser

Joined: Feb 2010

Posts: 113

Likes: 1

I thought that decel popping was a sign that the bike was running lean. I had that problem when I went to a ProPipe & AC change. Got rid of with a Master Tune.