The '09 FatCat will be called the "Boss". I live down the street from D&D and went in to talk to them about the new '09 FatCat and the tech told me that since the new redesign of the bike, they decided to redesign the pipe as well and rename it the "Boss" since it will only fit the '09 bikes.

Anyway, below is the information that he emailed me about the new pipes. What I am wondering is what anyone thinks about the new pipes and how they might perform as compared to the old FatCat? The only major difference that I saw was that the clearance from the transmission cover was decreased to about 1/4''. Other than that it looks pretty much the same. I'm just curious as to why it runs better without a tune with a high flow?




D&D Boss 2-1 for 2009 HD Touring
549-31/32

The Boss 2-1 is Specifically Designed for the 2009 model and will not fit 2008 and earlier models.

Kits available with Zippers Air Cleaner.

Best results were achieved with the 3” Max-Flow Air Cleaner and no tuner. Customer can order a 3” Max-Flow filter element only if their bike is already equipped with a
HD SE Hi-Flow air cleaner.

NO TUNER REQUIRED!
This system WAS tested with and without the HD Super Tuner. With the pipe and air cleaner only (NO TUNER) A/F did not change from stock in the cruise range (14.4) and the WOT (wide open throttle) runs proved the use of a tuner would do no more than jeopardize the motorcycles fuel economy and not enough of a power gain to justify cost. There was also no decal pop (aka backfire). However the addition of cams or other modifications will most likely require a tuner
(This is speculation as no testing was done other than stock).

System will ship with the wrapped perforated baffle. The customer can request the system with a perforated baffle.

No spacing of the floorboards was required.

The location of the mount bracket from pipe to transmission is designed to accommodate stock or taller than stock motors (it is the customer’s responsibility to correctly space the mount if using a taller than stock engine.).

This system will use special exhaust gaskets that will be provided with the system. We will also have them available for replacements. Screaming Eagle gaskets can be used but it is recommended that 2 are used in each port.

Available in Black and Chrome with Back or Slant cut

 

Pretty nice bump not to have to do anything else to the bike!

 

I was not aware that the afr went down to 14.4 on a stock application. Everything I saw in my SERT is around 14.7. So how did they lower the afr on a stock application. Or does the '09 have a lower afr . It would seem to me it is still runnning lean, around 14.7 in cruise. I am going off of a 2008 SERT disc, but still. I disagree not needing a tuner. If one knows how to tune their bike correctly you will not notice a big decrease in MPG.

 

I'm just curious if the flow will be any different than the old pipe.

 

I have seen A/F Ratios of 13.4:1 with Heavy Breather and True duals, Base map needs to be tuned in open loop so the 02 sensors dont screw with the mixture too much.

 

This thread and my thread then tie together because I noted the same or similar thing in an article this month from D&D and American Bagger magazine. No controller needed there either, go figure...

Pretty astounding if you ask me. I'm glad someone is finally publishing the results for these add ons..
Maybe because they don't market an EFI controller or are just being honest about it? Funny how that works huh?

https://www.hdforums.com/forum/touri...-this-one.html

ssfirefighter, would you please be so kind as to post your initial comments in my thread as a follow up?

 

Well I am real curious about this. I have a Super Tuner in a box ready to use and still intend to do so. I bet 14.4 is still too lean. I also am not initially using the Zippers filter but the SE one. Any thoughts from the experts here?