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2004 R1150RT Wideband O2 Sensors

What is the feedback parameter for closed vs open loop operation?

The O2 Sensor provides the feedback signal in closed loop operation ("control"). The Motronic uses it for more precise control of the Air-to-Fuel ratio whenever possible. A feedback variable is said to "close the control loop".

When conditions make feedback not possible, the Motronic runs 'open loop', providing a calculated amount of fuel for a given throttle position. This gets the job done, but less efficiently. In Open Loop Control the Motronic does not look at the results of combustion, the amount of O2 in the exhaust.
 
Although this is a forum for Oilheads, many are following the Wideband O2 project so I'm adding this report here as well as posting it in the Wethead section.
RB

Cold start data log for stock sent via email


... [then later] AF-XIED units received.

George's bike is an R1200GS LC (W) and he has offered to ride with the AF-XIEDs connected and logging data to his GS-911 Wifi.

It took me a while to get to analyzing the GS-911 information but I?ve gotten through it. The bottom line is that the AF-XIED is performing as it should. The key points:

1) The AF-XIED output is driving the BMSK correctly. The Lambda Sensor voltages are proper (200-800 mV).
2) The distribution of voltages measured by the BMSK is also correct?very nicely distributed between 200 and 800 mV.
3) The amount of time spent Closed Loop is high (newer model) and it is also correct.
4) There are no sensors that are displaying unexpected values.

There was only one real discovery, that is that the average Lambda Sensor Voltage while the bike was in Closed Loop operation was higher than I?m used to seeing?about 650 mV with the unit set on 8. (Can you compare the settings to the photo I sent?) This average voltage measured isn?t a function of the AF-XIED. It is based on The amount of time that the BMSK is reporting voltages near 800 mV versus the amount of time at 200 mV. What it means is that the bias point is perhaps 0.5-1% higher than the setting selected, indicating that the mixture is slightly richer than target (0.1-0.2 AFR). Because everything else is operating as it should, the higher average voltage isn?t an issue at all, more a curiosity to me.

The GS-911 on the R1200GSW reports different types of realtime values compared to the R1200GS. I?m working with Hexcode to understand why some realtime values that I?m used to seeing are missing. For example, if it reported the Lambda Control Factors (short term trims) we?d have a little more insight. It does report two injection pulse lengths for the GSW, compared to a one (base time) for the GS. Looking at the two pulse times on the GSW data, it looks correct and the differences side-to-side are small and reasonable.

Next steps for you would be to ride for a couple tanks of gas on setting 8, then a couple on setting 9, then a couple of settings 7 and 6. I realize this isn?t the best time of the year for this type of riding so you can keep the beta units as long as you feel like trying them.

Although I see no reason why the GSW won't benefit, the real question is this: now that we know the AF-XIEDs are doing what they are supposed to do, how does the R1200GSW respond to the fuel that gets added. In the case of many BMW motorcycles, there is a significant improvement in smoothness, roll-on torque, etc. Setting 6, 7, or 8 usually transforms the feeling of the ride. We will need to hear from several riders of GSWs to gain that insight.
 
I've been working on fueling with the owner of an R1200GS LC. He also has a GS-911 Wifi so is able to log realtime values.

The GS LC uses a fly-by-wire throttle, which means that you turn the throttle control on the right handle bar and the computer controls how far to open the TB butterfly. Below is a chart showing how far the BMSK opens the throttle on the vertical axis, based on where the rider positions the throttle control on the horizontal axis. This was an easy ride so the data only shows up to about 40% throttle.

There are several interesting things you can see:

--The sensitivity of the throttle is lower at small throttle angles, which should make the throttle easier to control.

--At idle, closed throttle, the computer opens the throttle up to 15% and varies it based on conditions.

--At small throttle settings at the handlebar, there are a wide range of possible throttle valve openings. How the throttle at 10% and the BMSK may use values of throttle opening between 4 and 7% (or degrees, not sure yet which units it uses)

I think this chart makes it easy to see that this bike's power control has new dimensions compared to R1150s and R1200s.

R1200GSLCThrotte.jpg
 
Nice work Roger :thumb
On my F800GS, first reports and my experience, were referred to as "snatchy throttle". Just a very small movement seems to go 0 to 4000 rpms. Many posting of mods that riders have done even to the "nautilus" shape of the throttle to calm things down. I have just sort of got used to it but it sure isn't the "linear" feel of an old carburetor.
OM
 
The Free-Air calibration did not completely restore my LC-1 to perfect operation after my +12V tap failed. After some internet searching I found a more comprehensive procedure that worked. Below is the full amended process. In addition to a vacuum cleaner I build a switch with spade terminals to use in place of the fuel pump relay. Since my LC-1 is powered on the fuel pump circuit (in place of the stock O2 sensor heater) I needed to be able to switch that circuit on without running the bike.

1. Open throttle fully and lock it at WOT
2. Connect a vacuum cleaner to the exhaust and switch in on
3. Put the transmission in gear rock the engine with the rear wheel until one cylinder is near the top of the exhaust stroke and both intake and exhaust valves are open. At this point you have fresh air flowing through the exhaust.

4. Replace the fuel pump relay with a switch.
5. Connect your PC to the LC-1 and launch LM Programmer
6. Turn the fuel pump switch on. Wait for the LC-1 to warm up (red led ON)
7. In LM Programmer press the Reset Calibration function. This clears all heater, free air and other calibration values. There is no confirmation dialog. Close LM programmer.

8. Turn the fuel pump switch off for 30 seconds.
9. Turn the fuel pump switch on
A) the Red LED flashes slowly while the unit warms up
B) next the Red LED flashes quickly for about 20 seconds, it is performing a Heater Cal
C) next the Red LED turns off for 3 seconds, it is performing a free-air Cal
D) next the Res LED turns on fully, signaling that all is well and the LC-1 is fully reset and calibrated

At this point you're done. The whole process took 15 minutes, start to finish.
-remove the vacuum
-replace the fuel pump relay
-relax the throttle
-put the transmission in neutral

At test ride confirmed good as new performance.

Getting the RT ready so I can ring her out a bit before heading south to the 49er rally later this month. I had a rough running bike with a bit of surging when I put her to bed last November. I just wanted to say thanks for these excellent instructions for a free air calibration of my LC-1. As you know my junction box has a built in power tap so I don't need to use a switch for fuel pump power but the procedure works exactly as described and mission accomplished. Bike fired right up and idled smoothly. Time to get an insurance tag and test ride. Thanks for all you do Roger. You da man. :thumb
 
It seems there are questions about the Oil Temperature Sensor (OTS) from time to time. Yesterday I moved the fuel tank back and installed a 10K Ohm potentiometer in place of the OTS, connected the GS-911 and adjusted the pot until the temperature list below showed on the GS-911. Then I measured the resistance of the pot and noted the number of bars on the RID. I estimate that the resistances are about +/-5% accurate.

The OTS is used by the rider to monitor Oil Temperature on the RID (Rider Information Display); and by the Motronic (together with the Air Temperature Sensor (ATS)) for cold starting and warm-up. Roughly speaking, there is about a 15% enrichment at 40F which tapers to 4% by 140F (or after a preset time since starting), at which time the Motronic runs in Closed Loop. The amount of enrichment and changeover to Closed Loop is also partly dependent on the ATS.

Degrees F142030405060708090100110120
Ohms9.8K8.1K6.4K4.7K3.7K2.9K2.4K1.8K1.6K1.2K980860
RID Bars000000000111
Degrees F130140150160170180190200210220230240
Ohms720580500430330280240210190160140120
RID Bars223345555556
 
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Nightrider is trying to identify R1200 Harness Adapter Cables with code "120314" on them. This code is located on the cable label on the last line. We have found a few of these cables that were wired "upside down" at the Control Unit end. Total effected harness Adapters is less than 28 units. Not all harness are incorrect. The most likely effected units would have been sold between 05-Dec-2014 and 01-Jun-2015

A visual check of wire colors should match between the Control Unit into the Harness Adapter.
Incorrect wiring is Yellow, Red, Black on the Keyed (double notch) side of the white connector.
Symptoms would be the AFXIED control unit showing only the yellow/green LED on solid after the units startup sequence and the engine running.

Any Rider with these cables can get a free exchange.

Effected bikes may be anything But R1150 and R1100. This includes R1200, F800, K-series, Husqvarna.

This can be published to the Forum(s).

--
Nightrider Support
 
Thanks, I hear you. I guess a lot have taken that approach. I'd like to keep the catalytic converter. From what I've seen on this site and others: grounding pin 86 says low octane, grounding pin 87 indicates a cat converter, and 87a says its an RT-ish bike (not positive about 87a). The pink '04RT plug is what I've got.

I'm planning to keep the converter and plug stock but shift the closed-loop mixture a bit richer. From GS-911 data I've logged while riding, the motronic spends at least half it's time closed-loop.

Hi Roger, you've been busy. In 02 or 03 I was in Germany with a friend of mine. We went into a BMW dealer looking for the olive drab cat code plug. The service tech asked where we are from. When we told him the U.S. He said"it's verboten". My friend Ed was a chief engineer on a ship. He had made a jumper wire for us previous to our trip to Germany. We just wanted the cat code plug to match. We found the OD green cat code plug in Nova Scotia. They were happy to send it to us. Fancy meeting you here cousin. Bob
 
Mixture Adaptation, Short/Long Term Trims, ECU Learning Exposed by the GS-911!

The Short Version
The GS-911 now reports long term trims for the BMSK which show beyond a shadow of a doubt that the BMW fueling strategy includes Long Term Trims, learned in Closed Loop by using the stock O2 sensor, which are applied to the entire fuel table. This means that the ECU learns about all fueling errors and most attempts to alter fueling on a stock bike. It learns about fueling changes (other than those made to the O2 sensor--e.g. LC-2 or AF-XIED) and brings fueling back to stock AFR.


The Long Version
For the past four years I've been explaining how the Motronic, BMSK and BMSX use the narrowband O2 (lambda) sensor to control combustion AFR in the Closed Loop area of the fuel table to accurate achieve lambda=1 (14.7:1 AFR for gasoline). It also allows those ECUs to learn how much correction is required throughout the Close Loop area and to therefore "learn" long term correction factors (mixture adaptations) that are applied throughout the fuel map--at idle, acceleration, all the way to full throttle--all the time.

Measurements reported throughout this thread have demonstrated the effects of this "learning" and many readers here have come to realize that our BMW motorcycle ECUs perform this powerful function. It allows the ECUs to adapt to changing conditions in the engine as it wears, as the fuel injectors and air filter accumulate deposits, imperfections and errors in all sensors, voltage deviations (even due to a failed alternator), fuel pressure changes, and even adapt to gasoline with ethanol.

This mixture adaptation also limits the ways in which you can alter fueling: modify the air temperature sensor and the ECU corrects fueling. Change the fuel pressure regulator and it learns about and fixes that too. Even modify values in the ECU fuel table in the onboard chip, and it corrects for that. However, alter the O2 sensor for richer or leaner fueling and the ECU obligingly shifts the entire fuel table automaticallY--e.g LC-2 or AF-XIED. (Another way to alter fueling successfully is to disconnect the O2 sensors & add a piggy back controller. This approach puts the ECU into a Limp-Home mode.)

In spite of the Bosch and BMW documentation mentioning mixture adaptation and long term trims, and even given the measurements of it shown in this thread and others, there are still many riders who aren't fully convinced. After all, until now there haven't been any gauges or displays which explicitly show the long term and short term trims at the heart of this "learning" capability.

Recently Hexcode SA, maker of the powerful GS-911 diagnostic tool, have added new realtime values to the long list reported for the BMSK ECU. In addition to the short term trims shown for the Closed Loop area (Lambda Correction Factors 1&2), the GS-911 now reports four new long term trims: Additive Trims 1 & 2 and Multiplicative Trims 1 & 2. The "1" trims are for the right cylinder and the "2" trims are for the left cylinder.

A colleague in the UK who has an R1200GS and owns a GS-911 and dual LM-2s (which can record AFR data and other info for both cylinders) with Wideband O2 sensors added to each exhaust. He took a ride the other day and sent in the LM-2 and GS-911 data, which includes a 13 second wide-open-throttle (WOT) run in 6th gear. This 6th gear "pull” shows for certain that long term trims exist and that they are applied to open loop fueling, right up to WOT.

Have a look at the table below. The data clearly shows the BMSK going open loop (highlighted in yellow) where the lambda control factors set to 1 (set to 1 there is no increase or decrease in fuel due to the immediate values of the O2 sensor) and clearly shows the application of the Long Term Multiplicative Trim at WOT. To understand the Multiplicative Trim, the number in the Injection Time column is multiplied by the number in the Multiplicative Trim column. Taking the first highlighted row, the 10.56 mS injection time is multiplied by 1.12 for the right cylinder and by 1.03 for the left cylinder resulting in Injection Times of 11.8 mS for the right cylinder and 10.9 mS for the left cylinder. In other words, the long term trim learned at lower power levels has been applied to this Open Loop area of fueling.

If you’re surprised that there is this much difference between the left and right cylinders, he confirmed that left and right cylinders had AFRs which tracked each other very closely by making an actual AFR measurement on both cylinders at the same time the GS-911 data was gathered.

Going a bit further, the multiplicative trim is not a single value for the whole but map but a table of values (how many have not yet been determined). There are 5 different long term multiplicative trims in this "pull" between 1800 and 4700 RPM. So the long term trim table is quite a bit larger than we'd expected.

There are also two long term additive trim types, for which there is a corresponding table of values. These additive long term trims affect small throttle angles and idle. The multiplicative trims affect cruising, acceleration and wider throttle angles.

[Summary]
This new GS-911 capability is an exciting development in the understanding of BMWs fueling strategy. It demonstrates clearly the complex ways in which its ECUs process data gathered in the Closed Loop fueling area and apply it to the entire fuel table, including acceleration and starting. At the moment, Hexcode has not added the collection of this data for the newer liquid cooled Boxers or for the older Motronics but the effect of the trims has been accurately measured on all bikes. If you care about this make sure to let Hexcode know that you’d like to see this data for your bikes too. (The BMSK is used on many different BMW bikes including the F800GS.)

As I receive more data from the field, I will add any important insights that are found.


GS911mixtureadaptationproof.jpg
 
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The bike in the table above shows an average trim of 1.08 for the right cylinder and 1.03 for the left cylinder. He has an AF-XIED installed on setting 7 and has measured it with an LM-2 showing about 6% added fuel.

If you subtracted that 6% from each side the trims would look like 1.02 on the right and 0.97 on the left, suggesting that the right cylinder naturally runs 2% lean and the left runs 3% rich. To me that seems like a reasonable spread. Our R1150s don't have dual O2 sensors so we could expect left right imbalances of this much or greater, which can't be "trimmed out" as on the R1200, a big plus for the 1200.
 
I’ve begun to lambda-shift (add either an AF-XIED or Innovate Motorsports LC-2) my new-to-me 2001 R1150GS and have found some problems and differences from the 2004 R1150RT that was the test vehicle for this thread.

On the RT, the O2 sensor is located ahead of the catalytic converter just beyond the point where the two header pipes merge. On the 1150GS, the O2 sensor is located inside the cat, between the points where the two headers enter the cat. This is a more distant location from the cylinder head, with different temperature. As a result, the Closed Loop period at idle is much slower (about 5 seconds, as opposed to about a second on the ‘04RT). The ‘01GS users an older, slower responding thimble-style O2 sensor (the ‘04RT had a faster planar-style).

While setting up and testing an AF-XIED on the ‘01GS, I realized that I could only get the GS to enter Closed Loop (key to having a functioning install) up to setting 5. Above that it flat-lined and registered a too lean mixture. The reason was that my O2 is original, therefore old and tired. Having my ‘04RT O2 sensor on hand, I swapped it in and found that I could get Closed Loop up to setting 9 on the GS, which is plenty rich.

I’ll do some riding now and see how it goes.
 
o2 SENSOR #'S oilheads

11 78 1 341 022 - GS & RT to 12//02
11 78 7 671 756 - GS & RT from 12/02

It appears both models changed.

I'm running an new earlier one in my GS and an AF-Xied setting of 6.
I guess I should update to be able to go into closed loop at that setting?
 
Hi GSA, I haven’t had time to work out whether is sensor age, wear, location, or technology.

Try whichever setting you want to use, take a long ride, check the error log. If you’re clean you’re good. Better yet take a riding log of realtime values and send me the log.
 
I did some riding at setting 8 and although the bike ran better, the old RT sensor (see prior post) doesn’t quite have enough juice and I got a couple “O2 sensor shorted to ground” errors in the GS-911 log. After that I cleared the errors and switched to setting 7. That did the trick and the bike pulls great from idle on up, with no errors

With the engine hot I checked the TB balance and noted that idle before the AF-XIED was 1100 RPM. On setting 7 the idle jumped to 1200/1250. The idle speed increase is a simple way to show that the AF-XIED is adding low end torque from idle on up.

While performing the TB sync to reduce idle back to 1100 I also checked the TPS setting using the GS-911, it was at the bottom of the green range with the engine off. Checked with a DVM (engine off), it was 301 mV. With the engine idling, the TPS voltage was 268 mV, likely due to TB shaft wear. The blue paint on the TB stops was intact but there was no paint on the TPS screws. After adjustment, the TPS voltage read 345 mV at idle, which is center of the range.
 
Read the entire post last night

Thank you all for your contributions, especially roger 04rt! Reading it explains the hard starting issue, then sparked my interest in optimizing the mixtures using wideband sensors in closed-loop mode. Where do I find one of those GS911's?. I have seen the website, wrote the company, ( no response ) but still confused which unit to buy.
I need WiFi, would like BT as well and have an '04? with round plug and 4 wires. Any used units out there that are known to work with the R1150 RT?

I have installed two extra bungs and the PLX DM-6 + SM-AFR with two sensors and one gauge. I see that the mixture is too lean to start reliably (15.1 or higher) too rich on warm-up ( as low as 12.1 ) and unbalanced during run ARF1 ( right cylinder ) at 15.1 while AFR2 ( left cylinder ) is at 14.4 My goal is to balance the mixtures as much as much as possible, then choose closed loop value that I like 13.8 for power :) and 15.7 for ultimate cruise economy. I have tuned a MotoGuzzi that way with an LC1 and faking the oil temperature sensor and those were the best values I could determine by just riding feel. Made all the difference. Now I would like to do the same on the R1150.

Any suggestions would be welcome.
 
The Motronic is pretty rich at start up. Start by making a plot using logworks 3 of the afr. Go from start to closed loop and post it here. It’s about a 5 minute log.
 
Since my two old narrowband O2 sensors only get me to AF-XIED setting 7 (5-6% added fuel)—and in fairness the bike runs well on that—I either needed to get a new O2 sensor or buy an LC-2 Wideband system if I wanted to try anything richer. I’ve also been curious about how this older GS (2001) is fueled compared to my former 2004RT (dual plug) so I opted to buy the LC-2, which includes the ability to datalog AFR in realtime and then plot riding logs. Plotting riding logs of AFR is the acid test for what a bike’s AFR is or isn’t doing and has been invaluable for me in the past, especially when I wanted to test the claims of a fueling mod, coding plug or Open Loop.

I already had all the miscellaneous parts needed for the project (OEM connectors, cable, sheathing and a serial to USB cable for programming) so I bought the LC-2. I’ve added LC-2s before and went right to it—pulled the tank, rear silencer and catalytic converter and got out the soldering iron, shrink tubing and PC. A few hours later the LC-2 was installed (hardest part was figuring where to lay all the cables), and set to lambda=0.92 (8% more fuel).

Once everything is installed, the Wideband O2 (Bosch LSU 4.9) needs a free-air calibration. Rather than pulling the exhaust a second time, I stuck a vacuum cleaner into the rear silencer, opened the throttle and bumped the rear wheel until I found a spot where one cylinder had intake and exhaust valves open at the same time and drew fresh air through.

Below is a photo of the finished install, the small controller sits on the air box. As time allows I want to run logs and see what differences there are for the three CCP options on my particular GS: European (no plug), US (yellow) and Swiss (beige).

2001R1150GSLC2.jpeg
 
I've run a few tanks of gas on the '01 GS with the Innovate LC-2 at lambda=0.92 (which is 13.5:1, 8% richer and the equal of 8 or 9 on the AF-XIED) and find I'm getting about 42 mph (summer) for non-highway driving. The pull between 1000 and 3000 is much stronger, no surging, the engine is smoother and around town I'm running a gear higher. Looks like I'll keep it at 8% richer.
 
The 2001 GS is running pretty good and I could leave well enough alone ... but who does that? As I've noted before in this thread matched fuel injection at all pulse widths and all RPMs is exactly as important as a good TB balance any time you're running much leaner than Best Power mixture which is around 13:1+/-. Further, on the Oilheads, unlike the R1200s, there is only one O2 sensor which means that the Motronic has no way to get the left-right fuel balance fixed with the sophisticated trims of the R1200. (As an aside, in a discussion with Hexcode, there are so many trims on the R1200 LC bikes that they don't think its worth their effort to report them.)

That means my next step should be to get the injectors cleaned and tested for matching. With that thought in mind, I've decided to buy a pair of matched injectors. If I was in Europe, Tills.DE would ship me a set, in exchange for mine for about 80EU. However, for US customers the only option is new R1200 units and adapters. After several email exchanges with Jürgen to clarify some points, I've decided to spring for a pair of them and test them on both the 2001GS and the 2017RTW (that's right, it too might benefit from a set of matched injectors).

After the install, I'll publish some plots of the initial fueling differences on the '01GS.

Here is a short summary of the discussion with Jürgen:

—Matching at a range of RPMs and injector pulse widths is critical to a smooth running engine at all power settings.
—Finer atomization is a smaller, side benefit that helps with starting and idle while the engine is cold.
—Well matched EV6 injectors would produce a smoother engine than unmatched EV14 (R1200) injectors at the tolerance limits. (That’s how important matching is.) They don’t offer matched EV6 injectors outside Europe.
—R1200 injectors turn on faster than R1150 or R1100 injectors but not as much faster as I’d estimated. (I will measure this myself by looking at unadapted AFRs.)
—Matching of injectors on a new water-cooled R1200RTW is also likely to improve the engine.

As a result of the clarifications, I’ve ordered a set of matched R1200 injectors and adapters. They should arrive in a few days.

They’ll get installed on my 2001 GS first and I'll make some measurements to see how much extra fuel they add before adaptation, then see what running differences I can detect—with the LC-2 set at 8% extra fuel (current setting)—especially at higher power and under acceleration. Later in the year I'll take the same injectors and try them on my 2017 RTW which is running with AF-XIEDs on setting 7.
 
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