My 09 has akropovic 4 into 2 into 1 evolution exhaust
I'm installing auto tune as far as bung placement if I am installing where all four go into one is optimal placement according to most I've spoken with. There is a two inch space under motor between motor and rear suspension linkage to mount bung at 9 , so not visible .the pipe at this point is not square with opening Therfore bung must be ground a a lot, if welded on at that point without grinding bung it will hit suspension linkage.
Ok can 02 sensor read properly if not at 90 degree inside pipe to exhaust flow. Or can sensor be mounted near 02 sensor akro welded in on exit of 3 and 4 cyl? not reading 1 and 2
Where is everyone mounting bung for at-200 auto tune
Pics?

* Last updated by: miket on 3/14/2015 @ 5:36 PM *

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Here's where mine was welded on. It is getting mostly a read on cylinders 1 and 2 (LH side), I'm sure. I'd like to see it placed back a little farther so it samples exhaust from all four cylinders equally. I was told by the Bazzaz guy that there is not much dif sampling two cylinders instaed of all four. Sounds a little iffy if you ask me. Romans had some good info about o2 sensor placement. PM him or maybe he will post here. It's a little more involved than how far back. Muffler reverberation and exhaust temp might come into play. One thing I remember is that the O2 sensor should be welded as much to the top of the pipe as possible (so the sensor points downward). This will reduce the rusting effect of condensation which ruins o2 sensors.

I'm guessing right where the pipe turns up toward the muffler would be best. ...seems like it would clear everything there, too. Maybe run up alongside the shock spring? That would work for my setup with the PC and Autotune under the seat. The wire would be vulnerable to stuff flying off the rear wheel but get a hugger and that risk is nominal.

* Last updated by: Rook on 3/15/2015 @ 1:16 AM *

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Dynojet now says bung goes 8" or less to head 4" preferred to get clean reading
He said do not mount where all 4 join into collector 30 in or so downstream fom head.
I am running akropovic evolution found perfect spot #3 cyl facing right side.Wires follow rad hose then snake to other side to mate with Pcv on left under fairing cover

* Last updated by: miket on 3/18/2015 @ 4:11 PM *

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DJ is a good resource to consult for their own products but I would not put full trust in them without having their advice confirmed by people who use the product. You will be tuning one cylinder if you place the sensor in a headpipe. I've been told cyl #2 and #3 are tuned richer than the outside cylinders. They should all be close in fueling but definitely not exactly the same.

If you are still following this thread, I'll ask Romans to get in on it. He has tuned with AutoTune and I'm sure he knows the best place for the sensor.

* Last updated by: Rook on 3/31/2015 @ 5:20 PM *

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Dynojet now says bung goes 8" or less to head 4" preferred to get clean reading
He said do not mount where all 4 join into collector 30 in or so downstream fom head.
I am running akropovic evolution found perfect spot #3 cyl facing right side.Wires follow rad hose then snake to other side to mate with Pcv on left under fairing cover

I would agree if you plan to tune each cylinder individually. 4 02 sensors ? Each cylinder has it's own fuel table so tuning one cylinder only cant be expected to tune them all.

If you look past the Turbo oil return line you can see 02 sensor bung welded in. Same place most all pipe makers weld in.

* Last updated by: Romans on 4/1/2015 @ 12:15 AM *

I guess I would put a bung 8 inches from the manifold on each head pipe. The best thing would be to have 4 o2 sensors and a separate AutoTune for each o2 sensor. I suppose you might be able disconnect 1 o2 sensor after the fuel trims have been recorded, then switch over to the next o2 sensor and so on for all 4 sensors. This would be a lot of switching around. At minimum, you might have one Autotune and one o2 sensor with four bungs. plug three bungs while tuning the fourth, then switch.

OMG, I'll just stick with sampling all 4. Looks like Romans has his o2 sensor where mine is but his points under the bike. Maybe if I really get into this, I'll try tuning each cylinder separately. I can't imagine trying that without having four o2 sensors hooked up to four different Autotune modules. ....I don't even know if that would be possible because the autoTune module is wired into the PC5 and I don't think there is more than 1 jack to connect them.

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So Romans, if you were going to ONLY have one o2 sensor, where would the best place be to place it? Right where you show in your pic?

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So Romans, if you were going to ONLY have one o2 sensor, where would the best place be to place it? Right where you show in your pic?

Sniff needs to be back just far enough that the gases from all 4 pipes get a chance to mix evenly. This is where most pipe manufactures weld in the bung for us. This will give us the best average.

Sure sounds like Dyno-Jet was giving advice for a 2 cylinder Hog ?

02 has to be positioned at an angle so the condensation drops off the 02 or if you keep it level in position, this horizontal move will capture the water and eat out the 02 eventually via the water is not leaving the unit with enough angle to drop water out of the unit.

Position of the 02 down the pipe is to meet each pipe in the collector so you sniff an average of 4 sniffs make one. You could use one pipe and run this as your average out to the other 3.

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You could use one pipe and run this as your average out to the other 3.

Yes you could. But, When I did this the map that was made was no where near the combined average Map. Error ?

There is a separate fuel table in the ECU for each cylinder. All four of these fuel maps are different as much as 4% in different area's throughout the map. Hence I would stick with the average of the four when making changes. Unless of course If was tuning all four cylinders separately.

We always assume just because the injectors are the same they will flow the same. That word AssUMe does indeed and can make a Ass out of you and me.

I used to spend allot of time in this study years ago. Everything from sensor error. Sensor readings compare, you name it. One study was to compare how far back 02 readings would affect readings of Atmospheric pressure. That along with how much water fills in the lowest part of the pipe and the time it takes to burn off. This info was tied to AFR readings during the time it took for water to burn off.

This is why I advise Do Not Tune until 02 sensor has been hot for one minute. Bike running again up to operating temp or your map will be shit. Evaporated Water plays havoc.

This picture shows Akrapovic Full Titanium Racing Exhaust. 2300 Dollar Pipe. Ouch. Look closely at bung Location.

Pic shows two sensors. Comparing readings. These would get flipped back and forth. Compares were made checking for Accuracy. Two AFR gauges both reading different. What percentage of error was the study.

This picture shows Akrapovic Full Titanium Racing Exhaust. 2300 Dollar Pipe. Ouch. Look closely at bung Location.

They did the same thing on my busa's Tsukigi exhaust. Not the manufacturer, the shop that welded it in before it was shipped. Shoulda had it done locally. I plan to have it removed and patch welded and then have a new bung placed in a better location.

Brings up another question.... How much obstruction or turbulence do one of these sensors (or plug bolts) cause in the exhaust? Is it worth it to cut and patch the improperly placed bung so the pipe is smooth inside?

What percentage of error was the study.

I'm curious, what was the difference in AFR between the two sensors which were run at the same time?

I gotta save this one. WOOOOOOhoo-hooooo! I'm hoping to take this a lot farther this summer!

* Last updated by: Rook on 4/1/2015 @ 8:31 AM *

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Goodshit, Romes. There is a coin-flat-coin stamping on the stock header, miket. That's where my 02 sits for the 200 screen use. I can swap to the screen-200 or use a remote 02 and read my maps this way. If I want to read map for map, I'd use 8 digital ohm meters and use them off of the stick and injector. See who in the ohm dept is working map for map. FoooooooUck the 02 BS where it sits. Use both meter(s) and 02; we go dialing in one pipe.

Look how the pc handles the harley. You'd have to have 3 more screen200'$ hooked into each pipe. (licking chops smilie) You'd have to drop in a safe map off the pc CD, watch the 02 and go from there (one pipe wonder) or run the 02 where they have that stamping for the euro4 kind of emissions and their 02 placement from the factory.

Take your pick, play the numbers, etc.

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