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Discussion Starter · #1 ·
I have a oz spec 109 with o2 sensors. I have just got some slashdowns and guess what...no o2 sensor bung, so the sensors will not go in and i have a FI problem. This will affect euro models, and maybe californication models. I have been on the phone to cobra twice now, and emailed shiploads of times, and they finally had a meeitng this morning with thier FI guys to talk about a my problem and devise a fix.
Firstly, the o2 sensor eliminators I found on this suppliers page ( link below ) DONT WORK, so dont buy em.
http://www.xtremerevolution.com/Sto...8&CategoryID=10&SectionID=85&ManufacturerID=0
Although shown for sale suitable for a 109, cobra say no, the supplier got it wrong.
Secondly, the 109 uses a closed loop FI system, so with the sensors disconected the bikes ecu defaults to a closed loop system and the FI light comes on.
I think this means a "limp home" mode, but i'm not sure. maybe someone more FI savvy then me can enlighten me.....
Anyway, a guy at Cobra named Bob ( I'm aussie, so it sounded like Baaaaarrrb to me ;-) ) said the closed loop default wont hurt the bike if i ride it and that they will email me in 1 or 2 days with a fix. I think they are working on a suitable sensor eliminator specific to the 109, with the correct resistance.
FYI the ecu only needs a correct resistor to be placed in line to emulate the sensor, it will then think all is ok and not freak out and default to a closed loop fuel map.
If there is any interest in this topic, I'll post the results of the fix when cobra email me in a few days, as it may be helpful to some other riders in time. :read:
 
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Discussion Starter · #3 ·
It would be interesting to see that closed loop default on a dyno, it should mirror what the rest of us here in the states are running. It may actually be a richer setting then with the O2 sensors, because as I understand the process, the O2 sensors measure for unburnt fuel and leaning out the mixture.

If I am wrong, JR or Perry or someone please correct me.

TAZ
 

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no California models do not have them either just Euro/Aussie/UK models according to the service manual. U.S. both 49 state and Cali do not have them but the Cali model does have some fuel evap crap built in the tank so lose a little fuel cap. Also Canadian models same spec a 49 state U.S. with no o2 sensors. The pipe maker should provide the bungs in the pipes for your model IMO. Most of the newer inline 4's are using o2 sensors and the pipe makers have the bung built in. the closed loop FI just fine tunes the mixture better at idle and cruise mainly, when your wacking on the loud handle or at cold start up both kinds still run on maps for fueling.
 
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Discussion Starter · #7 ·
Considering how tough Calif is on emissions, I'm surprised they have no sniffers. Cei la vie.
The cobra tech said that they purposely left bungs off, as the sniffer is preset to reduce fuel mix after analysing emissions in the header pipes. This is a primary o2 mix sensor, not a secondary "check" sensor installed after cats.
Problem is the cobra FI200r richens the mix to allow for free flowing pipes, but the sniffer detects the richer mixture and attempts to lean it out. The FI200r puts more fuel in, then the sensor detects it and attempts to lean out the mix.
This continues to yoyo lean/rich/lean/rich indefinitely.
Unless alternate sensors are found that are calibrated to accept a richer mixture, they create a problem for the bike not a benefit.
Best alternative ( IMHO ) is to remove the sensors and disable the FI light, ( I have just done this last night..) or to fool the bikes ecu into thinking the sensors are operating within their limits, and this is what the sensor eliminator or resistor will do. I'll try the cobra fix when they get it to me and see how it goes.
Until then, I guess I will run the bike on the default closed loop cycle fuel map with sensors out, and FI light disabled.
I do wish I had more decisive answers than the wishy washy guesswork I'm getting from cobra and others. I would have thought they would have it sussed before going to market with pipes........
 

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default should be open loop which is what our U.S. models run in all the time. closed loop brings the o2 sensor into play but they only adjust at idle and steady state cruise when you hammer it it goes back to running on the fuel maps just like ours do. I think someones feeding you some smoke. I know some guys who run the o2 cheaters which are just resistors to give the ecu a signal it is happy with on their hot rod cars and they work ok and get them past emissions testing.
 
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Discussion Starter · #9 ·
hey stevej you may be able to help on this one.
Just finished installing cob pipes, sans o2 sensors, as like I said there is no place for them.
Thing is, the bike wont start now. Only thnig chaged is pipes, sensors are removed, and FI light mod has been done, to ensure the FI light does not come on and stay on.
Now bike wont start. Just keeps crankin over and wont fire up.
Do you think the ecu thinks there has been a major FI failure and has shut down? Or maybe the fuel map the bike defaults to when it detects a FI problem is a simple "limp-home" map that doesnt have a warm up cycle in it? I'm really stumped now.
Might have to pull the pipes and take them to a specialist fabrication shop and have 02 bungs welded in.
Any ideas ?
 

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sure sounds like it quit fueling or firing. could be the puter shut things down if there was a hard code coming into it. I would personally want the o2 sensors functional if it were mine and I actually hoped the U.S. models would be closed loop, just a little more refined fueling. look at where and how they located the o2 sensors in the stock pipes and have a welder put some in. if they are standard o2 sensor size like a car has www.denniskirk.com sells the bung unless you have another source. :bigthumbsup:
 

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This may sound stupid -- BUT: are you SURE you haven't accidentally flipped the "kill" switch??
 
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Discussion Starter · #12 ·
all right.....time to fess up. It was nightime and I'd had a couple of emu's....so I missed it. After putting the pipes on, and bolting the bike together I tried to fire it up and nada. Thought it was the FI but it turned out to be the azzhole owner (me) who forgot to hook up the fuel and speedo connectors b4 putting the tank back on. :redfaced: :redfaced: :redfaced: :redfaced: :redfaced: :redfaced:
So to all who were puzzled by the dead bike and all, so sorry. Bike was good, mechanic was faulty. Now I understand why my wife used to tell me on our anniversaries that when I reach 40, shes gunna trade me for two 20's. Very basic mistake I didn't spot until I traced my steps and poked around a little the next day..anyway, onward and upward..... :bigthumbsup:

So, an update. Cobra are still trying to come up with an answer as to what to do with bikes with sensors. Said to call back late October. Yeah right, I have pipes NOW, and dont intend waiting until November to ride again :edit:
I read on this forum that most everyone considers that pops on decel = lean. I can tell you that on my bike, the pops = rich. I have a FI2000r and ran it with std settings. popbangpoppopbag on decel. Went from std to 3,4,2. Worse. Eh? Went to 4,3,0. Worse again. Started winding it back until I have 0, 0, 0 and she's a pearler ! Smooth, no popping on decel, and a lot smoother throttle. I reckon I could take even more fuel out if the FI2000r would let me. Going to dyno it in the next week or so, and see whats what. Does the FI2000r set at 0,0,0 mean it doing nothing ??? Not sure if i need it now. Going to pull the plugs in a week or so and see what they can tell me about the mixture.
The bikes default fuel map it reverts to when the o2 sensors are removed seems spot on without any further tweaking. Could be good news for any euro / Aussie spec 109s. Right now, she is hothothot. I put on cobra slashdowns, packed the baffles with glass, reversed the baffles so the perforations would pick up more gases, and then welded in washer to mellow the sound down. Pretty much what all the drags owners did to tame then down a bit. My pipes sound bloody awesome now, deep tone, quiet when needed ( early in the morning...) and they roar like hell when you give it a big twist. WAY better than the debaffled standard pipes for sure, and I know because I have some. IMO way better sound than std cobs also.
 

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glad you found the short circuit....between the ears! :D I would try and at least have her dyno'd with the sniffer up the pipe to verify where you are at with the AF mixture to be safe. I know with an auto it won't hurt it to run with the o2 sensor disconnected other than the annoying light but fuel mileage will suffer and they sometimes surge a bit going down the road at steady cruise. with a lot of drag pipes (2-2's) the bike developes a serious mid range hesitation from the mixture being too rich but unfortuneatly the Power Commander is the only FI controller that allows fuel to be removed as well as added for tuning.
 
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