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2004 R1150RT Wideband O2 Sensors

That's very interesting Roger, & obviously a lot of detailed investigation and work.


Roger, thank you for the detailed info!

So what have people been finding is the optimal AFR to run for an RT?

I feel compelled to comment :blah on how deeply that simple aspect intertwines with the provisions of "self tuning" and in particular (and my case) the MS technology.
Just to know what my old lump was doing with its original Bings (sorry for airhead content) I ran the original LC1 on the bike and documented afr behaviour at various temperatures and load/ speed conditions. To be fair, jetting and carb condition enters into results but with the bike running "very normal" I was shocked at how rich it would sit on cruise, and how lean it would transition towards on hard accel.
Everything to do with "inherent performance & behaviour" changed once the Bings gave way to injection and forced induction, but learning what AFR the bike likes is just a process of trying out different settings (on all states including idle, mid accel, hard accel, cruise, and decel) where all can be changed independent of the other. I find I can lean out to 16.5 easily in cruise with no surging or transition hiccup, as well have recently been playing with an economy tune to allow 87 octane while maintaining detonation free hard accel driving (our gas getting so expensive lately). I believe some megasquirters just seek out excuses to meddle with their tune, as it is perhaps too much fun:bliss
 
That's very interesting Roger, & obviously a lot of detailed investigation and work.




I feel compelled to comment :blah on how deeply that simple aspect intertwines with the provisions of "self tuning" and in particular (and my case) the MS technology.
Just to know what my old lump was doing with its original Bings (sorry for airhead content) I ran the original LC1 on the bike and documented afr behaviour at various temperatures and load/ speed conditions. To be fair, jetting and carb condition enters into results but with the bike running "very normal" I was shocked at how rich it would sit on cruise, and how lean it would transition towards on hard accel.
Everything to do with "inherent performance & behaviour" changed once the Bings gave way to injection and forced induction, but learning what AFR the bike likes is just a process of trying out different settings (on all states including idle, mid accel, hard accel, cruise, and decel) where all can be changed independent of the other. I find I can lean out to 16.5 easily in cruise with no surging or transition hiccup, as well have recently been playing with an economy tune to allow 87 octane while maintaining detonation free hard accel driving (our gas getting so expensive lately). I believe some megasquirters just seek out excuses to meddle with their tune, as it is perhaps too much fun:bliss

It has long been assumed that the R1100 and R1150 surge with light throttle, in Closed Loop. It is now seeming more likely to me that they surge in an Open Loop corner that is not well documented--namely RPMs greater than about 2000 and throttle angles less than 5 degrees. This is a very problematic area documented earlier in the thread by WallyG and myself. In this area, the bike alternates easily between a slight accel enrichment, and a slight decel enleanment--and it feels like it is surging there--and it is Open Loop.

To that end, I have now set my LC-1 to lambda = 1.08 which is about 15.9:1--very, very lean. There is no surging in cruise in 5th or 6th gear. As you would guess, the engine doesn't seem nearly as robust as at lambda 0.94 (13.8:1) but it doesn't run much differently from the stock 14.7:1 setting.

My next test is to see what the cruise gas mileage is with lambda = 1.08, out of curiosity.


BTW, Here were some recent fuel stats at lambda =0.94

2004 R1150RT
147 miles odometer 143 miles (google map) (odometer seems 3% high)
90 miles highway (60-80 mph) est. 70 mph average
53 miles local/stop&go, speed less than 50 mph
Top case and two side cases, windshield full up on highway.

2.877 gallons fuel consumed

lambda 0.94

smooth/brisk acceleration but not aggressive

average 143.2/2.877 = 49.8 mpg about 2/3 highway, 1/3 local with stop and go (subtract a mile per gallon if you want to add some uncertainty to the tank fill volume)
 
Here's an idea of how gas mileage is working out at lambda 0.94 (6% rich AFR). Put 143 miles on my bike the other day. Here are the stats.

147 miles odometer, 143 miles (google maps) (odometer error 3%)
90 miles highway (60-75 mph) est. 68 mph average
53 miles local/stop&go, speed less than 50 mph
Top case and two side cases, windshield full up
Air Temp 75F

2.877 gallons between fills (error allowance +0.1 gallons), 143.2 miles,

average 143.2/2.877 = 49.8 mpg (with error allowance 143.2/2.977=48.1 mpg)

Next Up: A test run of lambda 1.08 (AFR 15.9:1) 8% leaner than stock
 
Running the Oilhead Very Lean

The Innovate Motorsports LC-1 has two analog channels. One is usually used to simulate a Narrowband O2 output. The other analog channel is usually set to drive an AFR gauge, however it is possible to program it to simulate a Narrowband O2 output as well.

With that in mind Analog 1 to lambda = 0.93 (7% rich, 13.65:1 AFR) and Analog 2 to lambda = 1.08 (8% lean, 15.9:1 AFR). By means of a selector switch you can choose which mixture the Motronic is using, even while running down the road.

You can see in the chart below how easily the Motronic moves from Closed Loop at 7% rich to Closed Loop at 8% lean, and also how well it holds Closed Loop at either setting. Also on the chart is a reference line at 14.7:1 which represents the stock oxygen sensor setting.

duallambda.jpg


I had a chance today to make a 50 mile run with Closed Loop at the very lean setting of lambda = 1.08. Some observations:

--The Motronic easily adjusts to 1.08. This wasn't a very long test but under riding conditions over the 50 miles the bike seemed to be running normally, but with, for lack of a better phrase, a more anemic feeling.

--In cruise mode at speeds up to 60 MPH (top speed I could run for any distance on the roadway), there was no misfiring and no pinging. In fact I tried to make it ping with some uphill roll-ons and couldn't. The engine didn't seem to run any hotter than usual.

--Since my BBSs were set to idle at 13.65:1, I had to keep the fast idle lever up to idle at 1100 RPM. With the leaner mixture it takes more air to idle at a given speed.

--The engine performed "okay" but it took more throttle to start off than in the richer setting, the bike stalled as I let out the clutch to leave the driveway. Roll-on throttle while cruising, led to a very slight hesitation before acceleration

--At low speeds, throttle input exhibited some jerkiness during transitions from acceleration to deceleration that aren't there at all at lambda 0.93. The "hop" that can occur when the bike comes out of Overrun Fuel Cutoff was pronounced.

--The natural up-shifting point seemed about 1000 RPM higher than I grown accustomed to with richer than stock mixtures. It really did not want to be upshifted until 4000-5000 RPM. It just wasn't settled and ready to be shifted much earlier.

--Was there any surging? Yes, but only a bit and no more than I remember with a stock O2 sensor. Mostly light throttle in the range of 3000 to 4000 RPM.

--The course was 5 miles long with short stops and starts during course reversal. The 53.5 miles on odometer (51.9 corrected) was ridden mostly at speeds between 45 and 55 mph but top speeds were 65-70. Fuel consumed was 1.05 gallons +/- 5% which is about 49 mpg +/- 2 mpg.

Summary
In effect, this test was a side by side comparison of a richer fueled R1150RT and a leaner fueled bike. There's not question which is the more satisfying motorcycle to ride, the richer mixture by far.

Although the Motronic seems very flexible and able to run rich or lean of the stock setting with modified Lambda input, there is a big difference in the feeling of the engine. Richer mixtures (plus 4-6%) lead to a much smoother, slightly more powerful engine, especially below 4000 RPM, that "asks" to be shifted about 1000 RPM lower than a leaner one.

Leaner mixtures (minus 0-8%) lead to a more anemic feeling and seem to amplify whatever bad manners the engine exhibits (OFC hop, surge, roughness, hesitation). Overall it was an unpleasant ride.

By the end of the 50 mile test I was very happy to flip the switch back to lambda 0.94 where it's going to stay for the rest of the summer.
RB
 
Good Test Roger

Thanks for that info Roger and kind of neat to be able to switch (A-B) between AFR mixtures. Today I'm going to switch to a pink CCP and see how she runs at sea level at 13.1:1 AFR then maybe increase to 13.5:1.

Really like the switch idea.
 
For sure some diligent testing and documentation.
At the risk of offending (and I'm a high risk offender when it comes to discussing bike tech), you can have your cake and eat it too :blah
With Microsquirt for injection and ignition management, its a full meal deal where you get the best of all conditions and operating states to dial up optimum values that the bike and the rider want to enjoy (assuming you know what you're doing - many will attest to potential for knowledge overload or small detail snags that can hamper successful projects). In other words, your choice as to what afr at any rpm or load state, as well ignition timing. One has both 16x16 and 12x12 tables to work with.
I have an "in progress" tune where I might utilize 87 octane (has up to 10% added ethanol) at times, I have confirmed this to be very close to detonation free when I have water injection turned off - one just can't rely on finding the commonly available B.C. 94 fuel when on trips. That takes the stress out of heavy throttle roll ons, for more "no strings attached" riding. (& no, I don't sell the product).
Lorne
 
The megasquirt would be a great project. And you could get a native Wideband o2 capability. It seems that the amount of work required to get all the timing and fueling parameters worked out would be Herculean.
 
Hold on a sec, if I remember this post correctly you have a background in aeronautics, and obviously display a significant talent to figure things out - heading down that pathway wouldn't be all that challenging for you if I might render an opinion, but I don't want to be pushy.
I am a one bike owner at this point, but have a wish to push further into projects, I would love to MS a bike that starts out already being fuel injected and has the vast content of required components and sensors already in place and proven. The one thing that MS is good for is its adaptability - and when things surface that are somewhat off the page, there are highly educated and knowledgable forum participants that offer tuning help or program modification recomendations, even code changes and new parameter development just to make something work with the perhaps unique arrangements presenting.
In contrast, getting that all happening on a vintage airhead, with a beautiful fairing system that has to be left intact and can't be hacked - that is the crazy project to take on (and has been frequently pointed out by my patient family lol).
Who knows, I might be able to find a suitable donor bike, I'd love to get into a GS - so perhaps if one follows me home one day and I can hide it in the workshop for a while it might weather the storm of "You have two bikes on the go now!"
The old adage, "Nothing Ventured, Nothing Gained" is engrained into my project portfolio rational.
Lorne.
 
The Microsquirt/Megasquirt products seem very well documented, like you I suspect, I've read most of the site and even downloaded the source code. It looks to me like most of the project is straightforward. Our sensors would work, sometimes with coding changes, and I guess a connector to mate with the Motronic connector could be found. What I think I lack are the time and resources to develop the complex timing matrix that most FI vehicles use.

Therefore is seems to me that since BMW has a well balance VE map and extensive dyno experience with the motor to evaluate its timing needs, that I would be better leaving the timing alone and fix the fueling problem by lambda-shifting the O2 reference, in effect adding fuel everywhere. I suppose a hybrid approach would be to let the Motronic handle timing and develop the fueling with Microsquirt.

The biggest benefit to that would be additional fuel could be added into the Open Loop areas that naturally surge, more than just an amount created by the lambda shift.

If I did anything now, I might like to get one of BMWs newest models and see what it took to fix the fueling on it. The GSW seems like a really neat bike but after test riding it, it seemed that it to is affected by the mandates of the EPA and could be improved. It's got lots of HP but at small throttle angles the throttle & engine get very twitchy/touchy/frisky.

RB
 
Were on a bit of a vacation and I'm not spending much time online.
In actual fact, creation of the various tables for MS has become rather easy, certain Tuner Studio features make possible VE table refinement for example while driving, or from logs taken and run through programs on lap top after the fact. The ignition table albeit is the hardest to achieve maximum power/ efficiency from, when you are attempting to tune without provision of a dyno. It can be done, and in many cases provides very good performance to stock even in roughly formated examples that surface on MS forum discussions. However, just as I documented afr values prior to embarking on a MS conversion, the microsquirt module (or mega) could be interfaced on a bike either in a piggyback fashion on ignition sensors, or an alternate added connection - to fully document what the original BMW timing was over very broad operating ranges and such. Then those values could be used as starting values for the MS project. I suspect however that those values would be able to be edited for further improvements as things got underway. Its not really that complicated.
I believe what you are helping me to do however, is recognize what the next project I take on might be - an oilhead conversion.
Lorne
 
I've been reading other posts regarding behaviour of the Motronic system, and various seeming "masinations" that other riders may go through to smooth things out or offset crude performance at different points along its transitional states (and I thought I had a few slight hicups towards perfect operation, as I have developed different templates and assemblages of components that one might tend to appologetically admit if the need for total disclosure developed - but that seems to pale in comparison to these scenarios :blush ).

So, I admit that I am gaining significant interest in interfacing a Microsquirt onto an 1150, from a plug'n play standpoint. I may not have as much time to tinker as I would like but that is offset to a very large degree by the fact I've gone through the learning curve and should be able to skip ahead to "Go" rather than landing in jail so often as can be the case for megasquirters.

This makes perfect sense to me, perhaps I can develop the same acceptance by wife and kids :brow

Oh yah, I'm looking around at bikes.
 
For about the last month, even though my bike has been running great, I've noticed that my bike was taking progressively a little longer to start the first start of the day. For the past week it ran rough for 5-10 seconds after starting.

Having both an LC-1 and GS-911, I can measure all the sensors and the exhaust AFR, moment by moment, from before cranking and through start-up. So I hitched up the computer and recorded every start for several days. Maybe I got too much data but it showed that the exhaust was lean and also that the spark advance was staying at ZERO degrees for 7-10 seconds until the engine was running smoothly. So the leanness indicated to me that I might have a fueling problem and the spark advance left me thinking that maybe my HES was compromised.

The detail of the step by step tries to eliminate things isn't so interesting but by yesterday I was using the GS-911 in Hall Sensor Test Mode to see if the sensors were working and I was using the rear wheel with the transmission in 6th to spin the crank. I couldn't move the crankshaft smoothly enough with the plugs in so I decided to pull both primary plugs (stick coils in my 2004) something I last did about 6 weeks ago. It was then that I realized the left stick coil was 1/8"-3/16" higher-than-fully-seated. I ran all my tests and put things back together, making sure to fully seat the stick coils.

This morning, I took another data set and started the bike. It started right up as usual. The LC-1 indicates a little lean for about 7 seconds, but the spark advance (which is ZERO degrees during cranking) now goes to 5-7 degrees as soon (within one second) as the bike starts.

The fact that the Motronic holds the spark advance at zero degrees until the engine is running smoothly says that it has software that can detect time differentials between the HES sensors and conclude that the engine is misfiring or not running properly, a capability that I've read about for other ECUs.

When I ran the hall sensor test per the GS-911 instructions, using the rear wheel to turn the engine, which leads to some unevenness of the speed of turning the engine. I did see each sensor change state but not in a 1 2 1 2 1 2 sequence like I expected. It was more like 1 2 1 1 1 2 2 1 2 etc. I'm not sure whether this is expected or may be indicating some crosstalk between the sensors. I'll look into that more later.
 
LC-1 Installed on R1100RT

A friend from Vancouver who we know as Happy Wanderer agreed to be a beta tester for the BMW-AF-XIED on his R1100RT: R1100RT XIED Beta Report. The success of that inspired him to go whole-hog and install the Innovate Motorsports LC-1. GS Addict helped him with the installation and the workmanship is top notch.

r1100rtlc1install.jpg


The significance of this to all of us is that we will, as Happy Wanderer's time allows, start to get the first clear picture of how the R1100 makes its fueling decisions. Before going into detail, from the several test rides that HW has made to date, it's looking pretty clear that the R1100 and R1150 have very similar fueling algorithms. At first glance, it is difficult to tell the difference. Below is the first test ride made with the LC-1 set at Lambda 0.96 (4% richer or about 14.1:1). If I didn't know better, I'd say this data was taken from my R1150 it is that similar.

R1100firstafr.jpg


After riding for a few days at Lambda 0.96, HW increased the Closed Loop enrichment target by 2% to lambda 0.94 (6% total enrichment) and set up and took data from a cold-start to test ride on the road, that chart is below. A summary of what I can see from this and other charts he sent:

--Cold Start Enrichment: The R1100 has a similar start-up and cold start enrichment sequence, conducted as an Open Loop process. A difference to the R1150RT is that the R1100 seems to run a fixed time sequence from cold start where the R1150 shortens the time to Closed Loop, based on engine temperature, probably to reduce emissions. The amount of cold start enrichment seems the same as the R1150--10-15%.

--Adaptation Values: Based on several sequences HW sent me, and his reports, it is very clear that the Motronic MA 2.2 has learning adaptation, much like the R1150 and R1200. I can't say that the process is exactly the same, just that it exists. There are many who see the Motronic ECUs as simplistic, through the course of this project, I've seen many sophisticated capabilities in all models. This should not be a surprise since Bosch/BMW had had electronic fuel injection for about 15 years when the Oilheads were introduced.

--Acceleration Enrichment: Looking at the dips below the 13.8:1 line on the chart, you can see a significant acceleration enrichment, just like the R1150 and R1200. AFRs get to nearly 12:1 with a good turn of the throttle.

--Deceleration Enleanment: Likewise you can see bumps up to 14.4 or 15:1 showing that during mild deceleration the mixture is leaned by 4-8%.

--Overrun Fuel Cutoff: Just like with the R1150 and R1200, when the throttle is closed, the Motronic on the R1100 shuts off the injectors and the mixture shoots to the top of the chart, greater than 22:1.

--Rock Steady Closed Loop Fueling: HW is running E10 fuel during this test which shows that the Motronic has adapted (the fuel is 4% leaner than pure gas) its Closed Loop fueling to 6% richer than stock fueling (10% total enrichment considering the E10) and readily gets it back to 13.8:1 after acceleration, deceleration or overrun fuel cutoff.

r1100rt13.8cold.jpg


Thanks HW for the big effort you and GSA made to get this installed. I know as time allows you intend to take data with the Coding Plug out. When you do, the last of the Motronic's secrets will be exposed and we'll all know once and for all just what the R1100s and Motronic MA 2.2s do when the Coding Plug is removed.

Great work!
 
I heard from Nightrider and Beemer Boneyard that another batch of Controllers and R1150 cables will be available soon. R1200 cables are now in the design/check pipeline and should be available soon.


Hi Guys,
Took a little longer than I had hoped but we just received our first shipment of 24 of the BMW-AF-Xied units for the R1150 series bikes. You can see and/or order them here: http://www.beemerboneyard.com/bmwafxied1150.html
Stay tuned for R1100 and R1200 plug and play versions as soon as we can get the connectors delivered. Thanks!
Mike Figielski


PS,
These work unbelievably well. Took off the Power Commander I had installed on my bike for one of these and I won't be going back to the PC! It is that good!
 
Hi Guys,
Took a little longer than I had hoped but we just received our first shipment of 24 of the BMW-AF-Xied units for the R1150 series bikes. You can see and/or order them here: http://www.beemerboneyard.com/bmwafxied1150.html
Stay tuned for R1100 and R1200 plug and play versions as soon as we can get the connectors delivered. Thanks!
Mike Figielski


PS,
These work unbelievably well. Took off the Power Commander I had installed on my bike for one of these and I won't be going back to the PC! It is that good!

Mike,

Glad to here you're getting your first shipment and cables.

I am also impressed that you like it better than the PC III w/Wideband.

It is not well known that the main benefit of the PC III is the Wideband sensor, which Dynojet sets to 13.8:1. The PC III doesn't calibrate the Wideband so it can become inaccurate. Also since the 1150 adapts to the 13.8 setting it adds 6% everywhere through adaptation. So there is an invisible 6% in every cell.

That hidden 6% is only there after you ride for a while and the Motronic builds up some Adaptive Values and not typically when the dyno tuner does their thing. So it is easy to end up with too much fuel. Going further, the BMW fuel table has plenty of fuel already in the high power areas where tuners typically add fuel. So the typical PC Dyno tune adds fuel to an already rich area, and the the adaptive values add more.

Oddly the best place to add fuel on an Oilhead may be the 0%, 2%, and 5% columns above 2000 rpm. That is where the Oilhead is lean. But tuners never seem to add it there even though that is a spot that leads to surging.

Anyway, as you found out the BMW-AF-XIED gives you closed loop enrichment with the more robust, stock O2 sensor and is a one connector install. Simpler and smaller than the PC III w/Wideband, no computer programming. One potentiometer to set, usually at setting 7 or 8 on the 1150 and 1200.

RB
 
R1100RT OPEN LOOP FUELING, No Coding Plug (no CO Pot)

In the spirit of a picture is worth a thousand words, here is a chart I've been hoping (and waiting) to post for a year. You can look back one page for the Close Loop charts and commentary: HERE.

r1100noplugnocopot.jpg


Michael in BC, Canada, who has installed the LC-1 on his R1100RT was kind enough to reset his Motronic, remove his BoosterPlug, remove the Yellow Coding Plug (left the O2 sensor attached), and log a couple 40 minute test runs logging AFR data with his LC-1. There is a wealth of information in this small diagram.

First, the conditions:
Temperature: 70F
Coding Plug: None
CO Pot: None
O2 Sensor: Installed & Connected (but being ignored by the Motronic)
Motronic: Reset
Fuel: Premium with 10% Ethanol (4% lean compared to gasoline)

Looking at the chart above it is very clear how the R1100RT fuels without a Coding Plug. Since the CO adjustment target, if a CO Pot were installed, is 1.5% carbon monoxide (implying a gasoline AFR of 14.0:1) we can make an educated guess about how this chart will look with the CO Pot connected and adjusted, a test that will be made soon.

Although it would be more precise if I wrote these descriptions in terms of Lambda, but most readers are familiar with gasoline AFRs, so I have put everything in those terms.

First, I've carefully looked over two charts from this test run. Although the O2 sensor is installed and connected, it is clear that with NO Coding Plug, the Motronic does not make any use of the O2 sensor. This means that No Coding Plug is a fully Open Loop fueled R1100 motorcycle. I believe that a 30-87a (beige) Coding Plug will yield the same results.

Next, the idle AFR with no CO Pot connected is a very rich 12.4:1, were this motorcycle running pure gas at the time of the test the AFR logged would have been 11.8:1. At start-up on a 70F, the fueling is about 5% richer than that for several minutes while the motor warms up. Although this bike runs well with no CO Pot, it would be better to have it. An idle AFR of 13.8 to 14.0 would be fine.

Next, take a look at points 3 & 4 on the chart. Point three is the AFR while cruising at 40 mph and point four is while cruising at 65 mph, with AFRs of about 13.8:1 and 14.8:1 respectively. If this engine were running pure gas (what the fuel tables were designed for) that would mean AFRs of 13.2:1 and 14.2:1 respectively.

When the CO pot is adjusted to 1.5% CO, I expect those cruise AFRs with pure gas to be 14.0 and 14.4 respectively, effectively compressing the AFR spread. From this data one could conclude that the Oilheads were designed by BMW to cruise with an AFR in this range. This is well supported by the results several of us have seen with LC-1s and BMW-AF-XIEDs on our R1150s.

Looking closely at the AFR spreads between idle, 40 mph cruise and 65 mph cruise it isn't too hard to infer what the Motronic does with the CO Pot signal: it adds or subtracts an amount of time to the Injection Time calculation. In this way, it has a lot of effect at times when the Injection Pulse Times are short (like at idle and light cruise) and much less effect when Injection Pulse Times are long (like during acceleration and high-speed cruise).

In the No Coding Plug configuration, the Motronic still displays the same array of acceleration and deceleration enrichments and enleanments, still shows Overrun Fuel Cutoff and still shows a Warm Up enrichment sequence.

There's a lot to see and think about in this chart and sometime soon we'll have one run under the same conditions but with a CO Pot installed and adjusted. In the meantime, this points the way to a surge-free, best running Boxer Motor (R1100, R1150 and even R1200). Fuel it at 14:1, one way or another.

RB
 
Hey Roger, if you get a moment, could you please check posts 59 & 60 in the "Is There a Fix..." thread?
Thanks!
Paul S
 
Thanks for the excellent analysis of the data I sent you Roger. Have to admit I was confused at what I was looking at and for a while was getting convinced that the highway cruise section of my test ride (part 4 in the graph) was actually closed loop. After reading your report I now know it's just the ECU using the fuel map to get to it's prime directive; 14.7:1 AFR.

Rain and possible thunderstorms were forecast up here today but reality is things look pretty good outside at the moment. I am really curious to see what is going to transpire when I re-connect my CO trim pot so I think I'll get started on the next test! :dance

Installing and testing the Innovate Motorsports LC-1 wideband O2 sensor is really an eye opener. Over the past couple of years I and many others have chased down all sorts of suggestions on how to get these big twins to quit surging, end snatchy throttle syndrome and run like a big twin should. Theories and myths abound and I've tried most of them going back to Rob Lentini's work and documentation on up to the Booster Plug with a host of other things in between. The list is too long to get into here all over again. I had incremental successes but no lasting solution. Till now.

The LC-1 and the more user friendly plug and play solution the AF-XIED actually work unlike anything else I've done to date which only chipped away at symptoms. Best of all is having actual data from real on the bike testing and being able to log exactly what is happening in real time.

If we can debunk some myths and confirm some information about R259 engine fueling along the way I'm a happy camper. errrr wanderer. :thumb
 
Thanks for the excellent analysis of the data I sent you Roger. Have to admit I was confused at what I was looking at and for a while was getting convinced that the highway cruise section of my test ride (part 4 in the graph) was actually closed loop. After reading your report I now know it's just the ECU using the fuel map to get to it's prime directive; 14.7:1 AFR.

Rain and possible thunderstorms were forecast up here today but reality is things look pretty good outside at the moment. I am really curious to see what is going to transpire when I re-connect my CO trim pot so I think I'll get started on the next test! :dance

Installing and testing the Innovate Motorsports LC-1 wideband O2 sensor is really an eye opener. Over the past couple of years I and many others have chased down all sorts of suggestions on how to get these big twins to quit surging, end snatchy throttle syndrome and run like a big twin should. Theories and myths abound and I've tried most of them going back to Rob Lentini's work and documentation on up to the Booster Plug with a host of other things in between. The list is too long to get into here all over again. incremental successes but no lasting solution. Till now.

The LC-1 and the more user friendly plug and play solution the AF-XIED actually work unlike anything else I've done to date which only chipped away at symptoms. Best of all is having actual data from real on the bike testing and being able to log exactly what is happening in real time.

If we can debunk some myths and confirm some information about R259 engine fueling along the way I'm a happy camper. errrr wanderer. :thumb

You mention about the ECU using its map to get to the prime directive if 14.7, and what is clear from the data is that the Motronic Open Lopp fuel maps of NO CODING PLUG or BEIGE (30-87a) have no directive regarding 14.7:1 because these maps weren't designed to keep a catalytic converter happy!

I believe that the R1100RT no coding plug map, with stock intake tubes and pure gasoline and the CO Pot adjusted to 1.5%, were BMWs design for a great running boxer. So I'm going to go over paragraph 4 which I've pasted below some more.

Next, take a look at points 3 & 4 on the chart. Point three is the AFR while cruising at 40 mph and point four is while cruising at 65 mph, with AFRs of about 13.8:1 and 14.8:1 respectively. If this engine were running pure gas (what the fuel tables were designed for) that would mean AFRs of 13.2:1 and 14.2:1 respectively.

The data as present showed 13.8:1 for 40 mph cruise and 14.8 for 65 mph. Let me adjust those numbers for two conditions: ethanol and the misadjusted CO pot. E10 is 4% leaner than gasoline so if you were running pure gas the 40 mph cruise AFR would have shown 13.2:1 and the 65 mph cruise 14.2:1. That is the boxer design cruise range, except we have to make a correction for the unadjusted CO Pot.

At idle, injection pulses are 2.1 mS, but 1 mS is dead time so the actual on-time is about 1.1mS. That is supposed to create an AFR of 14.0:1 at idle (1.5% CO). You now idle at 12.4:1 so your bike is idling 14% richer than the 14.0 spec. That mean the injection time is 0.14 mS too long due to CO not yet adjusted. Taking that 0.14 mS and subtracting it from the 40 mpg gasoline measures AFR of 13.2:1 would bring the 40 mph AFR to 14.1:1, likewise doing the same to 65 mph cruise would move about 14.4.

With these adjustments, it strongly appears to me that BMW designed the boxer engine to run with an AFR between 14.0:1 and 14.4:1 in the cruising range and 12.8:1 when accelerating aggressively. (14.7 is only to make the catalytic converter happy. It must have been a sad day at BMW.)

The good news is that fueling the Boxer at 13.8 to 14.1 can be achieved easily now on the R1000, R1150 and R1200 through Closed Loop Lambda control.
 
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When will this wealth of knowledge be translated to simple terms for a guy like me to understand? I'm riding an 03 R1150RT that still has issues even with the Techlusion 259 installed.
Just need to know what device I need to make the bike happy!
Thanks, 64 and still learning or trying.
 
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