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Discussion Starter · #1 ·
I've got an 06 Dyna StreetBob coming (never owned a Dyna before) in a couple weeks.
The aftermarket exhausts have a fairly limited choice at this point (O2 sensor being the issue I think)?

I'm going to put a PC III on this bike and it has O2 sensor eliminator built in.
Since I'm going to eliminate the O2 sensor, I don't need pipes with the O2 sensor bung...

Will 05 and earlier Dyna pipes bolt up to this bike or has the new frame etc made it so the earlier pipes physically won't work?

Appreciate the info before I go down the wrong road and $$'s
 

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I think you're making a huge mistake by removing the O2 sensors. Those sensors are a tool used by the ECM to fine tune the bike while you ride. The closed-loop EFI system needs them to function and it is considered an improvement over the previous open-loop system. Some people assume that O2 sensors are just "smog equipment" and they are actually a vital part of a good EFI system.

There are several makers of exhaust for the '06 Dynas and more are coming each day. You can also buy O2 sensor bungs and have them welded into any pipe you want.
 

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Discussion Starter · #3 ·
JamieWG said:
I think you're making a huge mistake by removing the O2 sensors. Those sensors are a tool used by the ECM to fine tune the bike while you ride. The closed-loop EFI system needs them to function and it is considered an improvement over the previous open-loop system. Some people assume that O2 sensors are just "smog equipment" and they are actually a vital part of a good EFI system.

There are several makers of exhaust for the '06 Dynas and more are coming each day. You can also buy O2 sensor bungs and have them welded into any pipe you want.
JamieWG
I agree the closed loop system is supposed to be better. My concern is this system is a "narrow" band system and does not allow the broad range of correction that a wide band system does? Also, a friend said he tried SE slip-ons and a SE breather kit with a stage one ECM upgrade and it ran terrible. Eventually he had to get PC III and eliminate the O2 sensors to get it to run well? Even the PC III people said eliminate the O2 sensors because they will ALWAYS try to make it run lean in their current setup?
This is a tough one!
 

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roadhog60 said:
JamieWG
I agree the closed loop system is supposed to be better. My concern is this system is a "narrow" band system and does not allow the broad range of correction that a wide band system does? Also, a friend said he tried SE slip-ons and a SE breather kit with a stage one ECM upgrade and it ran terrible. Eventually he had to get PC III and eliminate the O2 sensors to get it to run well? Even the PC III people said eliminate the O2 sensors because they will ALWAYS try to make it run lean in their current setup?
This is a tough one!
The PCIII people weren't entirely honest with you. The bike will run lean in the current setup because of the software inside the ECM, not because of the O2 sensors. The problem isn't the O2 sensors, the problem is the Stage I download that your friend bought. The download programs the ECM to run very lean. The O2 sensors themselves are not capable of making the bike run lean or rich, they only collect data and return it to the ECM. The ECM makes changes based upon the map (download) that's been installed inside it. Yes, the O2 sensors are narrow band, but given the right map, even that small band will help keep the bike running great.

If you get a SERT, or a proper PCIII map, your O2 sensors will just be another tool used by the ECM to keep the bike running according to the calibration inside the ECM. That's what's nice about the SERT - it overwrites the software inside the ECM and you can get your bike running perfectly. The PCIII takes the data coming out of your ECM and alters it before passing it along to your injectors. I believe you have the option of using the PCIII and keeping the O2 sensors working. If not, then I would never buy a PCIII - I would get a SERT.
 

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JamieWG is correct the o2 sensors are only making small corections and will not make the bike run way lean. I have the sert and have done alot of reading on the closed loop system and how it functions. You set the the target afr for the o2 sensors. They only have the ability to move the afr up or down .5 in the scale. That is not very much. The problem with you friends bike is that the map that he had loaded has the target afr set to lean. One other thing is you also have the ability to turn the o2 sensors off in the sert for dyno tuning. So you could run pipes without the sensors with the sert if you needed to. But I would just put o2 bungs in and take advantage of the fine tuning that the closed loop system offers you.
 

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Think of it like this - Your eyes are your O2 sensors and your brain is your ECM. You see a chick walk by... your eyes don't decide anything, they just relay the info about the chick to your brain. Your brain then decides if she's lean enough..

I've woken up with a few and wondered if I somehow disconnected my O2 sensors by accident...lol.. but I don't think you'd want to do without them. Same thing on your bike. :beer4u:
 

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JamieWG Thats what I was trying to say.....LOL I think he might understand better now...:thumbsup:
 

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So far the new 2006 EFI system is a bit of a EFI boxmakers cluster, the O2 sensors need to be "fooled" into reading what the EFI box wants to tell it, there may be boxes out but they will be limited as to what they can do.

I will be getting a proto Gen III in a week or so to try out on the dyno.
Also, the nice thing about EFI is the ease of adding on NoS.

I'll post my findings soon as I can.
 

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Discussion Starter · #9 ·
floyd78 said:
JamieWG Thats what I was trying to say.....LOL I think he might understand better now...:thumbsup:
Thanks loads for the info on EFI and O2 sensors...I'm seriously looking at the SERT now.
However, no one ever told me if the 2005 and earlier pipes would bolt up to an 06 (assuming mid-control and I would have to drill and weld O2 sensor bungs)....will they fit?
 

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I don't know if they'll fit or not. The slip-ons from 05 will fit 06, but not sure about the head pipes. They changed the frame on the 06 models, so it's hard to say.
 

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Technically they should be compatable as the engine is the same baring the new frame has not changed that much on the two models. The only way to know for sure is to e-mail a pipe maker and ask if they changed anything other than the sensor ports. I would try e-mailing thunderheader to see if they had to change the layout or just add the ports. I would check butt I alreadey have pipes on my bike. Hey if you have not decided yet I will hake you a heck of a deal on a thunderheader. I have one with the 02 ports in it and its pretty much new.

Good Luck!!
 
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