Like the title suggests, I'm wondering which model-year range exhaust I should get.

On my penultimate day in Korea, I ordered a 2014 Fat Bob in black denim. That was before there were any pictures. Now I'm derailing my own thread.

Right, so I'm gonna pick it up in a couple of weeks. I've been looking at the Thundermax, and the Powervision, both with Auto-tune. I've decided to go with the Powervision, even though for months I thought I wanted the Thundermax. Derailing my own thread again.

Anyways, while reading about the Thundermax, I read that they suggest getting an exhaust for a 2006-2011 dyna, as it has bungs for the 18mm wide-band oxygen sensors, as opposed to the 2012-2014 dyna exhausts, as the newer ones have 12mm bungholes (hahahaha, yes, I'm an overgrown child).

Would this also be true for the Powervision? I'm inclined to believe so, since the Powervision uses the 18mm O2 sensors for the pro-tune.

The exhausts I'm looking at are both Vance & Hines systems, one being the big radius 2 into 2, or the 2 into 1 pro pipe. I know I'd get slightly better performance with the pro pipe, but I heard a big radius 2 into 2, and prefer that sound and look, and I'm not really drag racing this thing...professionally.

So, what I'm trying to figure out is, is there any real detractor to using the older model exhaust? As in location or angle of the O2 sensor mounts. I also read that the 2012-2014 style exhausts have updated mounts, supposedly deeper into the exhaust for more accurate blah blah blah...

So, can anyone enlighten to me as to what the real solution is to my mystery? I'd like to know before I commit to buying a $700+ dollar set of "finely tuned for performance and auditory pleasure" plumbing.

 

Get the ones for your year of bike and get adapters to fit bungs.

 

The PV uses 12mm for Autotune Basic and 18mm for Autotune Pro. Most PV users are happy with just the Basic Autotune. I bought pipes with 18mm bungs and used reducers that brought them to 12mm for the stock NB 02 sensors. Just recently I have upgraded to the PV Pro and took the reducers out for the Wide Band O2 sensors - this might be the way you want to go?

 

If you are just doing a stage one I would recommend sticking with the stock narrow band O2 sensors and using autotune basic. There really is no need for the AT pro with a stage one. If for some reason down the road you decide you need the Pro version you can use adapters like mentioned above or have 18mm bungs welded in you exhaust.

 

I'd go with the ordinary PV and the proper pipes for your bike. Bunch of reasons:

Adapters for O2 sensors aren't great because the sensor gets moved out of the gas flow and read lean.

The sensor ports are in the wrong place. For the >11 sensors they need to be near the head to be heated by the exhaust. For 12> the sensors are self-heated and need to be located further away from the head to stop them cooking.

The autotune feature is really not necessary. What they do is a very good job of maintaining whatever tune you start with. If its not great then it will accurately maintain a not-great tune. So, you need the bike dyno-tuned first, which kinda defeats half of the reason for auto-tune. You will get just as good results with a canned map (which are produced on a dyno) and auto tune basic to bed it in.

 

Can anyone post pictures of Vance & Hines Exhausts from both 06-11 and 12-14 styles, specifically: locations of the O2 bungholes?

Sorry for not being clear, I'm going to use the 18mm wide band sensors and the pro-tune. I'm only really asking if there is a difference in the mounting locations and/or angles of the O2 sensors mounting bungs between the two generations of exhausts.

AFAIK, you can use adaptors to use the 12mm narrow-band sensors in the 18mm holes, but not the other way around without metallurgical surgery.

So, should I get the 06-11 exhaust? Or is the new location of the O2 sensor bungs on the 12-14 exhaust so much better that I should get a new system and have new bungs mounted in their place?

In light of a previous post, if the new O2 sensors are heated, and should be further away from the heads, are the 18mm wide-band sensors heated as well?

I just want to make sure I'm doing what's right in the long run, and I plan to do more than just a stage one...eventually. I did get a 7-year unlimited mileage warranty, so getting too crazy is probably out of the question, at least until I pay it off.

 

Thanks dyolfknip, Chester, Foxster, and especially AlanSummrs (for emailing pics of his bike) for providing input. I ended up buying a used 06-11 Big Radius 2 into 2 from a forum member here. $300!!! I also bought a new SE Heavy Breather in black, also $300. They're all waiting at home while I'm away for work for a while. I only managed to get a little over 250 miles in 10 days on it before I left. I'm keeping busy, but am anxious to get back and open up the loud side of the bike.

I'm going to follow AlanSummrs example and just use Bassani adaptors to use the 12mm narrow band sensors in the 18mm ports. I also bought some FL-VIED-10s, from a forum here, for $60, to tide me over until I get the Powervision and Auto-tune pro.

 

Were the o2 locations different, or just the size?

 

The location was pretty close, maybe a slight difference. I'm sure there's a great scientific reason, but I doubt it makes that much of difference.

 

Will the length of the OEM o2 sensor wire reach the older pipe location easily? I have a '14 FXDB, & want a set of V&H Straightshots, but they only make them thru the '11 model year. If they will reach, I could use a reducer - unless someone thinks the sensor wouldn't be at the correct depth...?