02 Sensor for F4i on Aftermarket Exhausts?

I'm doing a bit of research for my girl's honduh for an aftermarket pipe.

What's the deal with the 02 sensor? Seems only the CA versions have it? What function does it have and why wouldn't it come on the 49-state version. I thought it monitored the percent of 02 in the air, which would adjust the mixture rich/lean depending on altitude. Is this correct? If so, I can't imagine that say an F4i in Colorado wouldn't benefit from it.

Secondly, it seems like most aftermarket exhausts (except for two bros and yosh) do not have a CA version for incorporating the sensor. What do people do? Eliminate it? How? Any ill effects by removing?

Thanks, just want to know before I go shopping on ebay

Just buy the 02 sensor eliminator from twobros. It's $15 and easy to install.

Well, posted about this before but my buddy ended up with the same problem. He bought a Scorpion pipe that came outside of CA and of course didn't have the provisions for the O2 sensor. He was told about the elminator, but decided to go to a muffler shop and weld a thread in the lower pipe. From there he just threaded the 02 and done!

Now, his FI keeps flashing. HOM says it could be the battery and some other folks say it's nothing much. To him, its flashing and its annoying.

I probably would try for that TwoBros sensor elminator.

Yea I have the sensor from twobros cuz I didn't want to drill a hole into the HM. Seems to work fine. No flashing lights or anything.

what does the sensor eliminator do though besides remove it I didn't really understand the twobros site description. I'm trying to understand what the 02 sensor does on the bike and what the effects are from removing it.

from the two bros site:
designed to read the Oxygen sensor under certain conditions and temporarily change the air/fuel ratio. The closed loop circuit has a very limited operating range, which is only in effect while holding a steady speed at certain rpm's and throttle positions. In this limited area, the stock system (with or without the Power Commander) will gradually and temporarily lean out the air fuel ratio in an attempt to achieve an air/fuel ratio of 14.7:1 (stochiometric). The Oxygen sensors can be disconnected but this will trip the F.I. dash warning light.

what type of conditions does this work and does it trip the FI light?

tiltedwrld said:

I'm doing a bit of research for my girl's honduh for an aftermarket pipe.

What's the deal with the 02 sensor? Seems only the CA versions have it? What function does it have and why wouldn't it come on the 49-state version. I thought it monitored the percent of 02 in the air, which would adjust the mixture rich/lean depending on altitude. Is this correct? If so, I can't imagine that say an F4i in Colorado wouldn't benefit from it.

Secondly, it seems like most aftermarket exhausts (except for two bros and yosh) do not have a CA version for incorporating the sensor. What do people do? Eliminate it? How? Any ill effects by removing?

Thanks, just want to know before I go shopping on ebay

Click to expand...

What is an oxygen sensor?
_ _ An oxygen sensor is a measuring probe for determining the oxygen content of the exhaust gas. Since the amount of oxygen in the exhaust gas indicates precisely how complete the combustion of the air-fuel mixture in the cylinders is, it is also the best starting point for controlling the air-fuel ratio.
Back

How do they work?_ _ _ _ _ _ _ _ _ _ _ _
_ _ _The oxygen sensor is strategically located in the exhaust system. The outside surface of the ceramic measuring tube protrudes into the exhaust gas flow, and the inner surface is in contact with the outside air. A voltage is generated at the interface which is proportional to the relationship between residual oxygen in the exhaust gas and that of the surrounding air. When this relationship changes, so does the voltage. This voltage is processed_ by an electronic control unit (ECU) into a control signal for influencing the air-fuel mixture through controllable fuel injection or carburetor systems. The exhaust gas composition is thus always maintained at that level which permits effective after-treatment by the vehicle's catalytic converter.

California models have this because of the emission laws here.

Cool Henry, but why cali only. wouldn't it really help at elevation where the oxygen is thinner? so other state like CO, UT, MT ect. should benefit from it right?

So what happens when you remove it and use the eliminator, what does that elimiantor do???

What do you want from me? I just plagerized it from another site. You actually think I know what I'm talking about?!

i dunno :infrandom

I just like tinkering with the bike, and buhhhhlieve me, when I tinker with hers, I GOTTA have an reason/answer

and another thing, why the FOOK doesn't this thing have swingarm spools????

Slowpoke,
I was just about to give you credit for knowing that info until I read where you got it. I don't know how the eliminator works, because it doesn't have a battery in it as far as I know. The O2 sensor is capable of producing about 1 volt, so a midlevel reading would be about .5 volt. If I were putting an aftermarket system on my bike, I would weld a threaded boss on my new pipe for the O2 sensor because I like for things to work as intended. Even if you can fool the bike into thinking the mixture is perfect and keep the FI light from coming on, you'd still be losing the benefit of that fine adjustment. Just my $.02.

Yes, yes. I am a genius. Ask me anything, ANYTHING I TELLS YOU! And I shall ask my friend...umm...Jeeves

urgh....so confusing the adjustment seems great, which is why I'm confused as to why cali only has it???

The threaded boss sounds like a good idea, then I read tdgstar's experience with it...

Henry, what did you use? And all the hundred's of other F4i owners with aftermarket systems, what did u use?

I know yosh and two bros have a ca model, but there's more exhausts on ebay priced low enough to make me want to figure this out.

I've got a Two Brothers High Mount (CA model). I'm pretty sure ALL aftermarket cans make a CA model.

Tilt -

All aftermarket cans do not have them. 2Bros, Devil, Yosh, M4, and I believe Jardine all make a pipe with the 02 sensor bung. If you buy a pipe without the 02 sensor bung, one can be welded on for $15-20. I did this with my old Renegade High Pipe (POS BTW). I've got an extra bung if you decide to go that route at some time. Just drop me a note.

02 sensor

I have taken this(02 sensor) off both my 929 and my XX. The O2 sensor kicks in only at constant, partial throttle openings in an attempt to lean out the cruising mixture. A dynojet plug or a 300Ohm resistor (across the two white wires)do the same thing---they prevent the FI light from going on. If you simply let the 02 sensor dangle in free air your light wont come on, but the bike will "flutter" cruising at constant partial throttle openings. My XX Akrapovic came with a undrilled bung--but with a PC--dynojet recommends using there plug---same deal on the 929. Personally, I wouldnt "dick" with welding a bung on--but I would invest in a PC3 to smooth out throttle response.

My 02

hehe

The Cali model is/was the only one with the O2 sensor due to stricter emission requirements (that the phuckers never test anyhow! ) - it has little/nothing to do with truly optimizing the air/fuel ratio since it's such a minimal amount and only at constant throttle. Most bikes going forward will have a 50 state model since more States are adopting the higher emissions requirements earlier than planned.
The eliminator kits solve the bung problem, however if you ever want to run Laguna and stock exhaust, now you have to plug up a hole in the OEM mid-pipe.
(if you look close enough at my avatar you can see the O2 sensor in it's stock bung on the TBR mid-pipe... )

slowpoke said:

Yes, yes. I am a genius. Ask me anything, ANYTHING I TELLS YOU! And I shall ask my friend...umm...Jeeves

Click to expand...

[basterdization]
Why do hotdogs come in packs of 8 and the buns in packs of 6?
[/basterdization]

Re: hehe

Chuci said:

(if you look close enough at my avatar you can see the O2 sensor in it's stock bung on the TBR mid-pipe... )

Click to expand...

How'd you do that I'm not so concerned about Laguna just yet, this is for my gf's bike and it will take some convincing to get her on the track. I guess I could always get a $10 stocker off ebay if that was the case.

I'm Just looking for the best solution when shopping for some used pipes. Just want to make sure I'm not doing anything that will fuck with the FI if I end up with a non-Cali slip-on.

Ok, I am reviving this thread since I just bought a non-CA Micron Serpent system and would like to know what's the best way to handle the O2 sensor issue.

Anyone with a Micron Serpent system on their F4i - please help!

You can go the resistor route,I bought the $15 plug in eliminator from dynojet /k&n for my 929 because it looks cleaner than tape and a resistor.Bike runs great,going on 3 years now.Gas mileage did drop a bit because of the 02 sensor leaning the mixture.I started off on 2 strokes where it's safer to run rich and besides,if gas mileage was a big issue to me,I would of bought a 50cc scooter.If you haven't already,buy a pcIII,you are going to need it with an aftermarket full exhaust.

Thanks! I have a PCIII. hell, I will take the exhaust to hare & get it dynoed after getting the o2 sensor eliminator there.