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2004 R1150RT Wideband O2 Sensors

Really???? You got game??????????????

your are wrong.
You may not appreciate the information but i (and if i may speak for the rest of us) do!
I don't ever read anything positive in your posts, just loud comments or controversial dialog and rough language.
Go back from whence you came, troll

wtf
 
Isn't it about time this post was moved to "Opportunities - Members and Vendors
Posts about events, products and services of interest because they have to do with BMW, motorcycles or BMW MOA members."???

I have stuff to sell too and I use "Flea Bay" as it's affectionately called on this forum. I got a gadget I made for oilhead clutches. I didn't think this was the place to make a coin. I might be wrong.

First off DY you need to get your facts straight.
- Roger is not making any "coin" off of the AF-XIED or the LC-1 and never has.
- He is not a vendor.
- He did the research, designed a solution and worked with a commercial producer (Innovate) to help get a BMW fueling solution to market.
- What Roger has done is help us all better understand and improve the ride ability of our oilheads.
- This thread is an ongoing technical discussion on O2 sensors and their role in engine management.

So yes, you are wrong.

Secondly, if you don't care to read about the wideband O2 sensor project simply unsubscribe from this thread and spare us all these ill informed complaints and opinions.
 
And in support

Although Bosch introduced the Motronic as an integrated fueling and ignition control computer, what follows are their specific comments on fueling, related to Mixture Adaptation. It should be clear from the following excerpts that Mixture Adaptation is a key, integral part of the Motronic operation. Of particular note for me was that Bosch has been using Mixture Adaptation (or you might call it self-learning) since the mid-1980s, nearly a decade before the first Oilheads.
RB

Excerpts from Bosch Mono-Jetronic - Motronic Documentation 1985-1998
The Motronic system is based on indirect measurement of air mass, called an Alpha/n ECU system. Alpha represents the throttle angle and "n" is the engine RPM. This system of indirect measurement of air mass operates with Adaptive Mixture control and super-imposed Lambda Closed Loop control to accurately maintain a constant mixture, without any need for direct measurement of air mass.

The microprocessor is the heart of the Motronic. It is connected by address and data busses to EPROM (which contains program instructions and data tables such as the fuel map) and to RAM which serves to store the Mixture Adaptation values (adaptation: adapting to changing conditions through self-learning).

If the Motronic sees deviations from Lambda=1 in the signals from the oxygen sensor, and as a result is forced to correct the basic injection pulse for an extended duration of time, it generates mixture correction values and stores them in an internal adaptation process. From then on these values are effective for the complete fuel map and are continually updated. This adaptation process ensures consistent compensation for individual tolerances and for permanent changes in the response characteristics of engine and injection components.

The mixture adaptation program is designed to compensate for the effects of production tolerances and wear on engine and injection-system components, including sensors. The mixture adaptation system must compensate for three variables: 1) Influences due to air pressure or temperature, fuel stoichiometry (ethanol content), injector flow rate and system fuel pressure. 2) Influences related to vacuum leakage in the intake tract. 3) Influences due to variation in injector turn-on delay. These three factors are applied to three map areas. Factor #1 is applied (by multiplication) to the entire fuel map. Factor #2 is applied additively in the vicinity of idle. Factor #3 is applied additively in fuel map areas of short injection pulses.

For mixture adaptation, lambda control factors are evaluated using a weighting factor before being added to the adaptation variables.

Limp Home: All sensor signals are continuously monitored for plausibility. If a sensor signal deviates from its defined plausible range, it means that the sensor or its connector is defective. In that case the sensor signal is replaced with a substitute signal that may effect drivability. For example a non plausible air temperature sensor is replaced by the value 20 degrees C. A fault in the lambda sensor results in a shutdown of the complete closed loop adaptive system but will continue to use any past mixture adaptation values if any have been stored. (Editor's note: a shift in the lambda sensor does not cause a fault, but disconnecting the sensor does.)


Next posts: Actual measurements of mixture adaptation on a 2004 R1150.

Thank you Roger - that is a good read and looking forward to more excerpts and coverage of the Motronic. Actually pretty smart stuff despite the manifestation of the problems being dealt with and faced on the 1150's and such.
Not sure Mr. DY intended to deflect what I thought might be a reactive response to my "carb" comments, but regardless - "Thank You" for the nice deflection.
In case my plugs for the micro squirt fuel/ignition management system I use is included in the "Opportunities - Members and Venders" category mentioned, just know that very little monetary benefit might bless anyone thinking in those terms (as it is the epiphany of low cost means to an end - just high insertion of learning curve).
 
Jes my 2 cents, having said that my mechanical knowage is quite limited. i say remove the cat at all cost because the heat source cooks the gearbox seals. and run a fuel managment system that elimitates the 02 censor, works for me. i use a 4 pot adjustable system, nothing fancy. and cost effective.
 
My '04RT never really ran quite right since new in '04. Over the years and about 41K miles I tried every fix I could think of and read about on forums like this with limited success. In the end it was Roger and his tireless attention to this inherent lean running condition and his coming up with the perfect fix, that being the LC-1 with wideband O2 sensor, that finally allowed me to experience a fine running motorcycle and I greatly appreciate it. I think it unfair to Roger to suggest that he is only in this for "coin" as I (we) know to be not the case.
 
A slightly different response
Dieselyoda- I've read a bunch of good stuff you've contributed but you're off base here. For example, when Jens developed the Booster Plug there was substantial discussion of it on this site and elsewhere explaining its theory of operation. That is exactly what Roger is doing here in explaining the adaptives in the Motronic and BMS-K to those who haven't read the original documentation- its almost like quoting a shop manual, not a sales pitch. Mike is the actual seller and isn't IMO hawking stuff- just providing an info statement about availability and given his well known long support for our hobby I doubt anyone is offended. Not to mention that no one could possibly get even slightly rich off this kind of item though it ought to be enough to keep most of us in beer..

To all - good debates are fun- let's keep it clean. We were all saying Happy New Year to buds only hours ago...

Disclaimer- I've used two AF-XiEDs on well tuned bikes (R1100S, K1200GT) and you sure don't need a dyno to feel the effect, it is obvious. In about 1200 miles of use have seen no obvious negative impact on mileage- meaning IF there is any effect at all it is somewhere between 0 and +/- 2 mpg, of no significance to me.
Am about to install one an an F bike and log data, also.

I look forward to seeing the data being posted eventually. Nothing like real data to educate and establish facts.

Like the carb discussion, too and the info on aircraft magnetos (but sure glad I don't own any old magneto bikes for daily use)
 
Moving along with some of the measured data on Mixture Adaptation. Below is the first of several charts, showing what the Motronic does when it is in Open Loop.

Here are the important things to see in the graphs. First, there are two lines
--The solid line is a test run with the Motronic fully reset, no adaptives, fuel pressure set to 53 psi (+11% richer) and a BoosterPlug (+6% richer, could have been any IAT shift device). I took a six minute warm up ride and measured steady state idle AFR. I show that point because it is one of the first adaptives to accumulate.

--The dashed line is a second test run with the Motronic fully reset, no adaptives, fuel pressure is 53 psi but without the BoosterPlug.

In the area between times 5:10 and 5:50, both plots are idling with the Fast Idle Lever fully down. The results:

FP Increase and BP AFR: 12.1:1 Open Loop

FP Increase, no BP AFR: 13.0:1 Open Loop

So the above are Open Loop AFRs for my bike, on that day. These are the baseline Open Loop AFRs for comparison a couple posts later after 10-15 miles of riding in Closed Loop.

On the chart, you can see where I flip the switch to connect the output of my LC-1 to the Motronic, the target AFR reached in 5-10 seconds is lambda=0.94 which is about 13.8:1. During that 5-10 second period, the Motronic is building something Bosch calls Lambda Correction Factors, amounts added to Open Loop fueling to reach the target AFR. The Motronic quickly ramped the LCFs to 1.06 and 1.15 to reach the target AFR. Later, the LCFs will be converted to Mixture Adaptations by the Motronic.

I'll show the Mixture Adaptations later chart, a couple posts from now.

adapt.open.loop.test.1.jpg
 
After getting the Open Loop AFR test runs made (chart repeated at bottom of this post), something not measured earlier, was the shift between the two curves, one with a BoosterPlug (BP) and one without. I was in a hurry so didn't take the time to locate the BP probe in the intake tract where it belongs and where I usually put it--so the results might be off by a percent. However when you compare the 13.0 AFR of the fuel pressure (FP) increase only to the 12.1 AFR of the FP plus BP, you get an AFR increase of 7% which is acceptably close to the 6% target for the BP.

As I started measuring the amount of Mixture Adaptation I got a surprise which I'll show before getting to the final results.

The chart below is a zoomed-in version of the dotted-line curve in the bottom chart. On the left of the chart you can see that the Open Loop AFR is 13.0:1. Then at 5:45 on the timeline, the switch on the LC-1 interface is connected, enabling Closed Loop. Closed Loop stays on until 6:15 for a total time in Closed Loop of about 30 seconds.

The the LC-1 was then switched to Open Loop at 6:15. My thought was I'd see what level of Mixture Adaptation had occurred in 30 seconds (about 1%). You can see what happened first when I flipped the switch to Open Loop. Because the motor was running at the time, and it was in Closed Loop, just happening to be ramping the fuel from rich to lean, it kept decreasing the fuel until the AFR reached 16.2:1. At that point, which is the limit of its Lambda Correction Factor (LCF) range, it ramped the fuel up until the LCF was at its neutral point of 1.00.

If you compare the AFR at its leanest, 16.2:1, with the pre-Closed Loop AFR of 13.0:1, you get a Lambda Correction Factor minimum of 0.80, which is a 20% cut in fueling. For the moment, I believe it is safe to assume that the LCF range is symmetrical at +/-20%.

We now know the range of LCF control: 0.80 to 1.20. Another secret of the Motronic MA 2.4 uncovered (and highly likely the MA 2.2).

Finally, if you look closely at AFR before and after the 30 second Closed Loop period, you can see a small difference, about 1%, 13.0:1 vs 13.1:1 in the Open Loop AFRs.

Next Up: A chart showing Final Adaptation results.
RB

P.S. As a side note, this is the same lower limit seen in R1200GS/GSA and F800S/GS data. Suggesting that the Bosch/BMW fueling concepts are fairly similar among all its models.

adapt.open.loop.adapt.full.range.jpg


Repeated Chart from Earlier
adapt.open.loop.test.1.jpg
 
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Thanks for this very interesting work and data Roger. Monitoring my 1100's behaviour using the LC-1 has been a real eye opener but the thing that really amazes me is how fast the Motronic is able to modify fuel supply to achieve a target AFR when an input changes suddenly. Also the fact that it is using values stored during closed loop adaptation for open loop control is something long suspected but now there's data showing that is what is really happening. With each new piece of the puzzle I am more convinced that shifting the O2 sensor input is the best way to achieve a favourable result.

Great testing Roger.
 
Time and Correction

So Roger, are you revealing a roughly 10 second time period where the stock Motronic is displaying a 20% correction on fueling?
If so, wow! That leaves a lot of room for improvement (I'm going to suggest, but perhaps I interpret your results wrong)
Apart from "Wall Wetting" where fuel hangs on intake track and intake valve(s) and which can create rich on decel and lean on accel for very short time periods as fuel readjusts/ coats the surfaces in question -"miliseconds" is the more common time period to be observing your tuning ecu's handywork. In fact, so quick that tuning adjustments can be hard to confirm without study of tuning logs (which scale in M.S. again). On a side note, the "X-tau" tuning adjustments are the most complex aspects I've encountered working with Micro S. but experts claim the 6 to 8 different tables (found in "Tuner Studio advanced") can fully eradicate any undersired shift in fuel ratio during hard acceleration/ deceleration even with long inlet runs between injectors and engine which is often deemed advantageous for atomization and power development.
However, seems you are laying the ground work to well substantiate the improvements available via your "unasuming" tuning device.
Lorne
 
So Roger, are you revealing a roughly 10 second time period where the stock Motronic is displaying a 20% correction on fueling?
If so, wow! That leaves a lot of room for improvement (I'm going to suggest, but perhaps I interpret your results wrong)
Apart from "Wall Wetting" where fuel hangs on intake track and intake valve(s) and which can create rich on decel and lean on accel for very short time periods as fuel readjusts/ coats the surfaces in question -"miliseconds" is the more common time period to be observing your tuning ecu's handywork. In fact, so quick that tuning adjustments can be hard to confirm without study of tuning logs (which scale in M.S. again). On a side note, the "X-tau" tuning adjustments are the most complex aspects I've encountered working with Micro S. but experts claim the 6 to 8 different tables (found in "Tuner Studio advanced") can fully eradicate any undersired shift in fuel ratio during hard acceleration/ deceleration even with long inlet runs between injectors and engine which is often deemed advantageous for atomization and power development.
However, seems you are laying the ground work to well substantiate the improvements available via your "unasuming" tuning device.
Lorne

Lorne, The time it takes the Motronic to go from a lambda correction factor of 1.0 at 13.0:1 AFR to 0.8 at 16.2 AFR looks like about 15 seconds. That time is the Closed Loop slew time, driven by software in the Motronic (as you know the LC-1 is 10X faster than a stock O2 sensor). The acceleration enrichment time which I will post in a few days is on the order of milliseconds.

I'm going to reread x-tau (X being the amount of fuel that initially sticks to the intake walls, and Tau being how long that fuel takes to evaporate off the wall and reach the cylinder) and compare it to a fairly wide range of "hidden" change of TPS rotational fuel mixture richening (and leaning) factors I've just found Motronic documentation for. In the charts underlying these Mixture Adaptation charts that I've posted I can also see the acceleration enrichments which happen fast and seem to be in the 5-15% range, the range mainly based on size/rate of throttle movement.

Though nothing like as flexible or visible as the MicroSquirt you're comparing, the Motronic has a lot more "talent" than it's given credit for due to BMW/Bosch keeping that knowledge secret. They would say it's proprietary intellectual property and they've published it but in such obscure documents that even the dealers don't seem to know it. For instance, who would guess that the Motronic MA 2.2 has two "Transition-Compensation factors related to engine temperature"?

I've also found in the documentation other factors that show Bosch has good command of the issues related to long inlet runs which the Motronic required due to its's first application being single-point injection. Btw, when launched for the mono-Jetronic in the mid-80s, the ECU had a 6 MHz clock, certainly fast enough for some of these advanced mixture factors, given that they wrote in low-level assembly code and had few OBD requirements.

The main emphasis here in these posts on Mixture Adaptation is to give those tuning their fueling more solid knowledge of the benefits of keeping Closed Loop operation, and of the type of changes that don't have long-term effect on fueling due to adaptation. My other point is that Bosch built a sophisticated injection system for its time but was hampered by EPA limitations that can easily be fixed by lamda-shifting the O2 sensor.

RB
 
Roger,

On the BB website, it says it will NOT fit any R 1100 bike except the R1100S.

Is that correct? I thought it would fit the R 1100 RT.

Please clarify.

Thanks
 
AF-XIED works on the R1100x but uses a universal cable. This requires the cut and splice of the black wire on the O2 sensor cable. The issue is that nightrider can't find a source of OEM connectors for the older R1100. If you can cut a wire and connect three posilock connectors it works nicely.
 
AF-XIED works on the R1100x but uses a universal cable. This requires the cut and splice of the black wire on the O2 sensor cable. The issue is that nightrider can't find a source of OEM connectors for the older R1100. If you can cut a wire and connect three posilock connectors it works nicely.

The AF-XIED will transform an R1100RT into the bike you hoped for in the first place. See my beta test report on the device from last summer here: http://forums.bmwmoa.org/showthread.php?56990-2004-R1150RT-Wideband-O2-Sensors&p=880407&viewfull=1#post880407
 
I see that Innovate Motor Sports has introduced the LC-2 ($189) as a replacement for the LC-1. They advertise the LC-2 as a self calibrating and temperature compensating unit, interesting and not a bad price. Of course I'll stick with my LC-1, for now.
 
Before posting the Mixture Adaptation results tomorrow, i want to discuss a Bosch chart, below, which shows another reason why Mixture Adaptation was designed as an integral part of the Motronic and BMSK fueling/spark ECUs.

As has been described, the alpha-n ECU design relies on throttle angle as an indirect measurement of air mass. And looking at the clip from Wikipedia below, you can see that Bosch's adaptive technology significantly predates Motronic and BMSK. The only real surprise is that BMW keeps this information so well hidden.

On the chart below, which is specific to the Motronic alpha-n ECU but not specific to Oilheads, you can see graphically adaptations importance:

--At low RPMs and small throttle angles a 3% change in throttle angle requires a 34% change in the amount of fuel injected to maintain a constant AFR. That means that a small TPS sensor error, or small change in air flow through the throttle body could result in a significant mixture error, leading to the conclusion that precise Mixture Adaptation is a necessity for accurate fueling at light loads.

RB

From Bosch Motronic documentation:
volumetricefficiency.jpg


Mono-Jetronic (1988?1995)--from Wikipedia
Digital fuel injection. This system features one centrally positioned fuel injection nozzle. In the US, this kind of single-point injection was marketed as 'throttle body injection' (TBI, by GM), or 'central fuel injection' (CFI, by Ford).
Mono-Jetronic is different from all other known single-point systems, in that it only relies on a throttle position sensor for judging the engine load. There are no sensors for air flow, or intake manifold vacuum. Mono-Jetronic always had adaptive closed-loop lambda control, and due to the simple engine load sensing, it is heavily dependent on the lambda sensor for correct functioning.
The ECU uses an Intel 8051 microcontroller, usually with 16 kB of program memory and usually no advanced diagnostics.
 
Alpha N

I have avoided working with Alpha-N, seems to ignore so much of what is taking place on an engine. With "Speed Density" actual conditions are being utilized plus for a turbo'ed condition it is much superior, as loading and boost can be all over the map so to speak, even with a throttle setting that is constant. Some squirters have adopted the blended "Alpha-N/ S.D." tables which can help with engines having poor "map" characteristics but are boosted. Our boxer engines having two cylinders might qualify for that concern but I have found stability even at ultra low idle states such that I have no concerns.
Each item you provide here seems to help paint a picture of what the Motronic is striving to do, and how under certain conditions the unwanted oscillation might take place.
Really appreciate your informative approach.
Lorne
 
--At low RPMs and small throttle angles a 3% change in throttle angle requires a 34% change in the amount of fuel injected to maintain a constant AFR. That means that a small TPS sensor error, or small change in air flow through the throttle body could result in a significant mixture error, leading to the conclusion that precise Mixture Adaptation is a necessity for accurate fueling at light loads.

RB

Hello Roger,
I think the above quote from your last post pretty well sums up the reason why many of these oilheads exhibit the annoying tendency to surge at slow speeds and why the narrow band O2 sensor with its characteristic slow response time does not much to alleviate the problem. This also leads me to think that the LC-1 controller with the fast response wideband O2 sensor is the best option for use with these machines.
 
Widebands are fine but cost and complexity are generally going to put this approach out of the range of the average owner who probably can't handle the work let alone understand all of the technical issues. For those who can- well, why not if it interests you?

I had my first wideband as a monitor on a track car so long ago I forget when, exactly. It allowed me to keep an eye on what the very limited aftermarket ECU of that era (simple 8X8 map, no closed loop) was delivering to a motor that would grenade immediately if it got too lean. So its real purpose was to allow watching the "richness" to ensure enough for combustion cooling at the outer edge without it getting so rich it reduced power excessively- and to keep EGTs from literally melting the wastegate of that boosted motor. (It would go over 1750 degrees almost instantly even a bit on the lean side of EGT control- actually in the high 13s AFR- but that was also where it made max power)

As is pointed out by Roger the real issue especially for oilheads may be the INDIRECT measurement of a critical material, air (oxygen), by a TPS rather than by a direct air measurement device.
Its predictable that indirect measures are likely to have the largest per cent errors at low and fluctuating flows.

One obvious way to cover such imprecision- much as I did (above) for several years- is to provide some extra fuel to avoid the lean side issues, whatever they happen to be.

For myself, I don't want to repeat the work that went with track vehicles or my modified street cages on a bike. Plug and play OTOH is pretty appealing.
 
Roger,

On the BB website, it says it will NOT fit any R 1100 bike except the R1100S.

Is that correct? I thought it would fit the R 1100 RT.

Please clarify.

Thanks

Sibud, you are reading the description of the R1150 unit on our website. We also list an R1100/K1100 unit which will work for your R1100RT here: http://www.beemerboneyard.com/bmwafxied1100u.html .
It is a splice in harness for now as the stock connectors are hard to find and very expensive. It is a simple splice into the O2 sensor wire lead, NOT the main wire harness. We provide 2 Posi-Lock connectors and 1 Posi-Tap connector. It is a very easy install even though it is not a true plug and play at this point. Well worth the effort as it will transform your RT. Thanks,
Mike
 
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