O2 Eliminators

[Rasher]

Has anyone tried O2 eliminators yet :question:

So far I am happy the clutch mod has increased low down power and removed stumble, but was not sure if this mod also removed the closed loop fuelling, so I have grabbed a pair of O2 eliminators off E-Bay to test. Assuming the fog clears I may go and try them today.

Has anyone else tried these :question:

I know the real "fix" for all issues is a decent flash, but so far the clutch mod and the eliminators has cost me under £40 as opposed to £450 for a flash, and the savings are likely to put a set of de-cat headers and a different can on the bike as well. Hoping the stock over-rich fuelling will result in decent running with the exhaust changes.

The O2 eliminators should also improve throttle response at smaller throttle openings, but could also affect fuel consumption - will update once I can get some decent comparisions done - with UK weather at this time of year it may be a while.

 

[zamfield]

Are you running a Power Commander too?
Won't removing the O2 sensors through the stock programming out and make it run worse - without a flash or Power Comm?

I'd like to hear some ride report using the o2 elim. before I buy but, I've not even seen them on ebay here in the US!

 

[Don in Lodi]

There don't seem to be any claims of benifits to running those as stand alone tuning aids. If you don't have a programmable PCM to compensate for all the info that's being missed, I don't think it's going to be a plus for you.

 

[Rasher]

I spoke to an ECU unleashed dealer who told me the closed loop area is up to 40% throttle below 5,000rpm - an area I spend a lot of time in, and he reckoned the elminators would help, and he was right ::008::

Just been out for an hour and the difference is very noticeable, the throttle response is much nicer at lower settings, I also have the clutch mod on a switch and switched back and forth, I would say the eliminators on their own resolve the "stumble" as well as giving a nicer response to small throttle openings, in fact riding normally is much better - just check how far you really open the throttle when your riding normally, I bet it is rarely more than 50%.

The clutch switch "on" definately still gives a bit more, but the eliminators have added a bit more.

Contrary to popular belief you don't only gain from eliminators with Power Commanders, what happens is in the closed loop area the O2 sensors adjust the mixture to keep it very lean (for emmisions regs) they tend to be needed when fitting a Power commander otherwise you tell the PC to add fuel to richen the mixture and hte O2 sensors just tell the ECU to reduce the output (don't forget the Power Commander only adds (or removes) fuel by altering timings post ECU

So if the ECU says "10 squirts" at x rpm / x throttle and the dyno man decides to add 2 to richen it, the O2 sensor detects the richer mixture and the ECU then sends out an "8 squirts" signal to "correct" the fuelling, to which the PC3 adds 2 to, and your back at the "10 squirts" you had already decided was too weak.

The O2 elminiator on my bike will fool the ECU into thinking the mixture is where it expects it to be so it will not add or remove any fuel from the base map, this is not exactly a perfect solution, but so far my clutch switch and eliminator mods have cost me £40 - a lot less than a £340 flash - and some flashes do not alter the closed loop settings.

Once the headers are fitted it will be back to the dyno to see the results

Certainly it feels better from my arse dyno, which is all that matters to me, the engine feels crisper and more responsive, it won't be more powerful under full throttle, but as I don't twist the throttle to the stop all the time that is irrelevant, it is now a bit better when riding normally.

Need to do more miles to get a better idea of fuel consumption, but it is not likely to be much worse, the run today was about on par with what I normally get from a solo ride on the local back roads, it may be 1-2 mpg down but definately no more, possibly no less, unlikely to be any better though.

Another cheap option either alongside or instead of the clutch switch, I will continue to run both, but either one in isolation makes the stumble a lot better and pulling awy feel smoother.

 

[fjrden]

Where do the eliminaters go any pics?

 

[Rasher]

Where do the eliminaters go any pics?

Just follow the wires from the exhaust pipes, they actually go a long way up behind the side panel on the RHS and the cabling is a real tight tangle, but it is not too difficult to find them and get the wriggle room need to pull out the wire and push in the eliminator, a bit of a fiddle, but anyone should be able to do it in 10 - 20 minutes.

 

[Rasher]

Done a few more miles now and have a better idea of the difference, or as much as I am likely to get without a very long run.

The throttle response is much better from down low, so much so I am probably using barely more than half the throttle opening and a few hundred rpm less than before when crusing about - for the same pace.

In sports (or clutch mod mode) the throttle response is very agressive, it makes the engine feel far stronger, although in reality it is just giving more grunt for less throttle opening so if you really yank the throttle it is not any different, but when riding steadily (or even normally for most folks) it feels stronger and smoother. The other effect it does have though is making the top end seem a shade flatter as using more revs / throttle gives less of a gain than before.

It definately has not removed the stumble, I spent time turning the clutch mod off and on, and when pulling away the stumble is still there but I am sure it is not as bad as it is without the eliminators, but I did still prefer the clutch switch mod turned on.

Touring mode is now noticeably better, I always hated it before, but it now feels a shade more useable to me and when on very narrow lanes today (almost mud tracks) it was handy to use and did not feel as lethargic as previously, may also be useable for me when "toruing" or at least pottering around towns, or stuck on the motorway.

The bad news is I am fairly certain it has dropped a couple of mpg, really need a lot more time to be sure and ideally a proper long run, various short tests imply it is not much worse and I think when going at a fair pace what you lose from the extra fuel being lobbed in the motor you get back from having more grunt at lower revs and with smaller throttle openings. Where I think it loses out most is sat at a steady cruise, only did a shortish test, but I reckon at 80mph it has dropped from 47-48mpg to about 45-46 mpg.

Definately need a weekend away to really see the fuel difference, but I think @3 mpg is the penalty for this mod, well worth trying for yourself at the price if you do want a bit more low down grunt / better throttle response. Although if you spend most your time at more than 40% throttle or above 5,000rpm it will make no odds, and for anyone who just tends to use the bike for thrashing about this is likely to make you very happy ::008::

It is not as good as the clutch mod which achieves a bit more with no penalty, but I am happy with the combo and unless the MPG turns out to be a lot worse I iwll leave them in - also when I fit the de-cat headers they may make a bigger difference, gonna try the headers with and without eliminators when I get them.

 

[viewdvb]

I fitted the O2 eliminators to my Multistrada and they did everything you describe so that must be typical. The Multistrada had crap fuelling below 3000 revs and they almost cured it. My UK (European?) S10 has as near perfect fuelling as I have ever experienced so no need for mods. The US version seems to have all the same symptoms as my Ducati hence the improvement for you. One thing is certain - the O2 eliminators have the most beneficial effect for the least expenditure, are easy to fit and are completely reversible if necessary.

 

[Rasher]

The US version seems to have all the same symptoms as my Ducati hence the improvement for you. One thing is certain - the O2 eliminators have the most beneficial effect for the least expenditure, are easy to fit and are completely reversible if necessary.

I am in the UK with a UK bike, surprised you have not noticed the off idle stumble, on mine as you pull away you get the clutch out and then as you go for drive the bike almost stalls. Also in 2nd / 3rd (like overtaking very slow cars / exiting roundabouts) there is a delay from opening the throttle until the bike pulls cleanly (ECU holds back throttle until about 5,000rpm so as my wrist is asking for more the bike is telling me to pi55 off) both are very well cured by the clutch mod though.

I guess if you tend to keep the revs up, or are quite gentle with the throttle at low rpm's neither would show up as mutch, I tend to try and ride the torque with large(ish) throttle opening at low(ish) revs, typically short shifting between 4k and 6k most of the time, this and being two-up quite a lot really seems to highlight both "faults"

 

[Wanderer]

Howdy,
Rasher, you can't reduce engine RPM and still get the same MPH (I'm assuming the pace you mention is MPH). The motor is geared to the transmission and the transmission is geared to the final drive. Unless you change something along that path no matter what else you do RPM vs MPH will always be the same.
Later,
Norm

 

[viewdvb]

Rasher - you are probably right about why I haven't noticed any stumble. I am easy on the throttle on pull away and I don't generally use large throttle openings for the fuel economy reasons plus large throttle openings imply large acceleration and there isn't too much scope for that on English roads without also caning the brakes and tyres. I certainly don't keep the revs up unecessarily and I am 2-up 95% of the time. I really can't detect what you describe so there must be some real random differences bike to bike. I'm pleased I got one that behaves well. Then again, it may be a difference in personal sensitivities. After a Multistrada, anything was going to seem smooth. Are you still running the stock exhaust?

 

[Rasher]

Howdy,
Rasher, you can't reduce engine RPM and still get the same MPH (I'm assuming the pace you mention is MPH). The motor is geared to the transmission and the transmission is geared to the final drive. Unless you change something along that path no matter what else you do RPM vs MPH will always be the same.
Later

I probably meant MPG, what you get is more power from less revs, so for the same rate of acceleration I can shift a bit earlier, clawing back some of the losses of the richer fuelling.

See what happens when the headers go on next ::013::

 

[Rasher]

See what happens when the headers go on next ::013::

Initial tests are all good, wnet for a brief spin after fitting the headers, hard to gauge exactly what is going on as I only did a few miles with the O2 eliminators last week and am not sure how much of the current feel is the eliminators and how much the downpipes.

I "think" it has added a bit more ooomph everywhere, but can't be certain as the low down response with the O2 eliminators was pretty impressive, but it has certainly not got slower off the bottom end :exclaim:

Up top it has definately gained, cannot be sure about actual peak power increases, my instinct tells me there is noticeably more power, what I know is it definately hangs on to the power longer, whereas it felt flat past 7k before,as if power was tailing off it now pulls harder and into the red without feeling like the power is tailing off very much. It also was upsetting TC1 on full throttle in second which I have not noticed before - but it was only 7c and up until now the weather has been much warmer, so it could be down to a bit less grip.

It also seems to run nicely, it will hold 2k in 4th (30mph) nicely and pull smoothly from there, crusing at higher speeds also felt good, only did a handful of miles so will have to see if anything odd happens over time.

Will get back down the dyno as soon as I can to check it all out.

 

[Rasher]

Did some more miles today and got a quick dyno session in, overall the bike still feels very resonsive with the current setup, not got around to running with O2 sensors and headers, but as I am pretty sure they will just put the low throttle fuelling back where it used to be I am in no hurry.

Did another 70 odd miles with a mix of A-Roads, narrow mud splattered back lanes and a bt of town work, on the way out with mainly A-Road and quite a bit of traffic holding my speed down (a lot of 55-55mph whilst waiting for overtake opportunities) I managed a 50mpg average, the way back involved a bit of town riding just to see how it felt. I definately like the T mode a lot more with the eliminators, it is now far more useful for town work and gentle cruising.

The dyno pretty much confirmed what I had hoped for, the over-rich top end is now about spot-on with the motor breathing a bit more freely, and with the clutch mod the low down fuelling is also pretty good on full-bore. Seemed little point doing loads of part throttle runs as the dyno man said your unlikely to be way off to the point oof damaging a motor with an exhaust change - but he did a few part throttle runs and watched the fuelling - seemed OK. If I plug the O2 sensors back in he is fairly certain it will just revert to the horribly weak running the emmisions tests dictate.

One thing I did not do last time was a high gear run, it seems 5th gear makes more power than 3rd and more power than the clutch mod mode.

Overall I gained about 4 BHP, with the before and after 3rd gear runs (with clutch mod) showing 86.9 (Stock pipes) and 91.0 (Arrows) with a gains from around 3,000rpm and a good extra dollop of power from 6k upwards (it feels quicker up top on the road too) this is the 3rd gear comparison of stock headers Vs arrow headers with the clutch mod

Below is a 3rd gear run and 5th gear run (no clutch mod) and a 3rd gear run with the clutch mod, another thing I noticed is there is an even bigger gain with the clutch mod now, on OE pipes the power went from 41BHP to 49BHP at 40 in 4th, it now jumps to about 53BHP.

5th Gear is giving a respectable 96BHP - More than any twin cam GS, with the exception of tweaked press bikes this also shows the clutch mod is off limited value if your cranking along in upper gears making a switch even more handy, you can use the switch in slower stuff when your up and down the gears, but if your able to keep the motor above 5k rpm or not drop below 4th gear the switch can be turned off.

I could have spent all day there doing runs in each gear, and each mode, with switch, without switch etc. etc. but I now know the bike is running fine, both by seat of the pants, and on the dyno.

If I am concerned about mpg I may go back to running the O2 sensors, as these operate at up to 40% throttle and 5000rpm, but I am not so sure the mpg is much worse now, and as I am struggling to work out if it has worsened, it obviously cannot be a lot worse - and probably not enough for me to want to lose the rather sharp throttle response I now have.

An end can may add another 3-4BHP (Arrow claim 2BHP for a can alone and 8BHP for the full system) but as I don't like noisy pipes as they annoy me when cruising I may not bother. I am sure an end can and a good remap would make the bike even better, but I have gained power across the rev range and considerably improved throttle response for under £200 (and saved some weight)

 

[mcbrien]

I installed the same 02 elliminators and agree it works well with the clutch mod
and also helps with the sloppy throttle when in touring mode . ::008::

 

[RED CAT]

Interesting. No one has mentioned elevation. I know in the UK, you are pretty well running at Sea Level. Here we are mostly in the 4000-5000 ft range. Just wondering if the gains would be as good. Also, any idea where to get the O2 eliminators in North America? Tks. ::26::

 

[Rasher]

Interesting. No one has mentioned elevation. I know in the UK, you are pretty well running at Sea Level. Here we are mostly in the 4000-5000 ft range. Just wondering if the gains would be as good. Also, any idea where to get the O2 eliminators in North America? Tks. ::26::

I bet the Greek fella who flogs them on E-Bay in the UK would ship you some, I think he is single hadedly keeping their economy from going under.

I would guess the closed loop system keeps the bike piss weak whatever altitude you are at and the eliminators will richen it up nicely, dunno if this will give a better / worse or same gain at altitude - but for the relatively low cost worth a try.

 

[viewdvb]

Interesting. No one has mentioned elevation. I know in the UK, you are pretty well running at Sea Level. Here we are mostly in the 4000-5000 ft range. Just wondering if the gains would be as good. Also, any idea where to get the O2 eliminators in North America? Tks. ::26::

As I understand them, they simply mislead the ECU into thinking that the bike is running lean enough so that it stops trying to reach the built-in super lean condition. These figures are all relative to air density so it shouldn't make any difference what altitude, the ECU will simply take that into account when setting the mixture to the new "fooled you" setting.

 

[ash1]

Hi,
I have got the ecu unleashed & pc v with auto tune. If the eliminators are fitted can the closed loop area be mapped & changed to a particular afr?

Thanks
Ash ::022::

 

[imoxygenuho]

thank you