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2004 R1150RT Wideband O2 Sensors

Yes, the sensor on my '04RT is just ahead of the cat probably same as yours. I looked at the same diagram of the exhaust system on oemparts. Hey, what can I say? It was a year ago I looked at that new R1200R and I could have sworn I saw a sensor after the cat. This wouldn't effect my decision to buy one or not. No way am I ever going to buy another new beemer or any other new mc for that matter. Just to much dinero or should I say Loonie, eh.:doh
 
Highway Trip

Made the highway run yesterday. Data below.

Data Points: 2,100

Driving RPM Range: 3,700 to 5,000 (roughly)
Injectors Fully Off: 3.3% of trip

Closed Loop O2: 47% of trip, up to 80% in steady throttle cruise

I observed two new things from this trip.

1. The highest correlation for closed loop operation is when the TPS (Throttle position) is steady. (I guess that shouldn't be a surprise.)

2. The Motronic will go into Closed Loop mode while the bike is accelerating through the gears. As each new gear was engaged, the Motronic started in Open Loop operation (richest mixture) but would go Closed Loop (leaner mixture) while accelerating. This surprised me. When the bike is cold, it remains Open Loop. My thinking is this is why the motorcycle seems more driveable cold vs hot.

(I can only post one photo at a time so the shifting charts will follow.)

In the chart below (RPM, TPS and Lambda On/Off) you can see the effect of accelerating through a few gears in traffic on the left side (to 5th gear) of the chart (and dealing with changes in traffic speed). On the right half of the chart (to 6th gear), the bike is in "throttle-locked" cruise, more or less. It is in closed loop a lot of the time.

If anyone has an old and/or dead R1150RT O2 Sensor, please PM me. I would like to purchase it for the connector so that I can build a Wide Band replacement system. Thanks.
 

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Cold Engine Takeoff, bike feels strong, no sense of lag or surge. Lambda sensor is Open Loop.
 

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Warm Engine Takeoff, bike feels okay but slightly hesitant before shift to next higher gear. Lambda sensor goes Closed Loop (lean) in middle of acceleration. (Numbered points are: Throttle Open #1 &4, Clutch Engaged #2 & 5, Lambda Closed Loop #3 & 6.)
 

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Warm Engine Highway Acceleration, bike feels good but note that Motronic goes Closed Loop (lean mixture) in middle of acceleration. (Numbered points are: Throttle Open #1, Acceleration #2, Lambda Closed Loop #3.)

I am surprised at the times during acceleration at low and high speeds/RPMs that the Motronic chooses to go Closed Loop.

I've ordered an Innovative Motorsports LC-1 and will see what the feel of a richer Closed Loop AFR is. I expect to notice it most under warm engine start-off conditions under 3,500 RPM.
 

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Grounding Question

Yesterday I pulled the tupperware and exhaust, removed the stock O2 and dropped in the wideband LC-1 O2 sensor. Also scoped out how and where I will locate and connect the LC-1 "computer". It looks like it will fit nicely under the tank strapped to the frame, in front of the ABS. Will add a photo later.

There are multiple grounds to connect. Does anyone have experience with the best location for adding new ground wires?

Also installing Beemerboneyard metal QDs at this time since the tank is off.

Once installed my plan is:

1) Ride with the O2 sensor function NOT connected to the Motronic to get baseline data ON AFR/Lambda.

2) Attach virtual-narrow-band O2 function with Lambda=1 to verify that it runs correctly and stays Closed Loop as per the stock O2 sensor.

3) Adjust Lambda upward and downward in small steps to measure its effect on warmed-up driveability.

RB
 
LC-1 Installed

Yesterday I finished installing the Innovate Motorsports LC-1 Wideband O2 Controller on my 2004 R1150RT. Before describing the project and my first test ride impressions a couple points:

--When the valves are adjusted, idle set and the throttle bodies are balanced my 1150RT runs pretty well.
--My preference is that the motorcycle is as near stock as possible, maintaining EVAP canister and Catalytic converter.
--BMW and Bosch (Motronic, O2 sensor, ABS) design well and know more about these systems than I ever could.
--The aircraft that I flew for a couple decades had three main performance modes: Full Rich (takeoff and climb), Best Power (fastest cruise, AFR< 14) and Best Economy (greatest range, AFR > 15). Although all modes were "smooth", if you over-leaned Best Economy the engine would start to stumble and eventually ping.

--Ethanol fuel: The 2004 RT uses Open Loop fueling tables that were designed for gasoline with a stoichiometric AFR of 14.7:1. In the Northeast US, gasoline with up to 10% ethanol is about all that's available, which has a 14.1:1 AFR. This suggests that the stock Open Loop fueling tables run about 4% leaner than the BMW/Bosch designers planned for. (In Closed Loop operation when the O2 sensor is used for control it automatically corrects for the E10 fuel.)

--My '04 RT feels strong while the engine is cold. After warming up, the motor seems reigned-in a bit from 2,000 rpm to 4,000 rpm (and reminds me a lot of how my plane felt with a too-lean mixture). After warming up the Motronic allows Closed Loop operation with the O2 sensor which means the AFR (in gasoline terms) is toggling between an AFR in the low 14s to an AFR in the low 15s. And since the cylinders are independent of one another, one cylinder is bound to be even leaner than the other.

My project goals:
1) Open Loop: Richen fueling tables to compensate for gasoline with Ethanol added. For this I've used a BoosterPlug which claims 6% richer mixtures; and ethanol fuel is about 4% leaner so I'm guessing about a 2% gain richer mixture overall.)

2) Closed Loop: Richen the stoichiometric target by the smallest amount needed to remove the sense of leanness between 2,000 and 4000 rpm. The Innovate Motorsports LC-1 provides a programmable Narrow Band output to the bike's Motronic ECU input.

Project:
LC-1 Kit: Bosch Wideband O2 sensor, LC-1 Controller, Cables, Programming Software, Serial Bus programming input.
Also purchased: PC Serial Bus to USB Converter (since none of my computers have serial inputs)

1. Pull the fairings, remove the fuel tank (replaced QDs at same time).
2. Drop the exhaust, remove stock Narrow Band O2 sensor, install Wideband O2 sensor.
3. Install LC-1 controller on right side of bike, under tank on frame, near alternator.
4. Connect Wideband O2 to LC-1, routing cable using same path as stock O2 sensor.
5. Route LC-1 cables to left-hand side of bike, along frame, and make connections to power, ground, AFR meter (part of LC-1).
6. Route LC-1 programming cables to area under seat behind electrical box.
7. Connect LC-1 Narrow Band output to Motronic by cutting and splicing into the original O2 sensor leads.
8. Leave O2 heater wires connected to the stock Narrow Band sensor, temporarily, until I can figure out what the Motronic needs to "see" in order to enable Closed Loop and not create a fault code. Tie wrap O2 sensor to frame.
9. Program closed loop AFR target to 14.2 which was a guess about where to start.
10. Start the motorcycle, attach the GS-911, let it warm up, confirm Closed Loop operation and make sure there were no Fault Codes in the Motronic. EVERYTHING WORKED! (Photo below shows #1) AFR switch points, and #2) that the bike entered Closed Loop after warming up.)

The installation took about 6 hours spread over a few days. Someone experiencde could do it faster but it was the first time I'd pulled the tank and exhaust. I got out for a test ride late yesterday.

Riding Impressions:
The course was over winding, hilly, straight and flat roads for about an hour. I am truly excited by the first results. Knowing that I'm looking for a positive outcome I wouldn't blame you for being skeptical. I haven't collected data yet to back up my impressions. But I'm not selling anything, just trying to enjoy my bike more. Here are some observations.

--No hesitation, no feeling of being reigned-in or surging. No popping, pinging or backfiring. In brief, no negatives.
--Very smooth acceleration in every gear at high and low RPMs.
--Good roll on throttle response at high and low RPMs.
--Very good cruise at low RPMs (2,500 to 4,000). 5th gear was a pleasure at 40 MPH or so. 6th gear, from memory, was easy at 50.
--Smooth at high RPMs.
--Warmed-up bike using Closed Loop modes feels just like the cold engine--strong and smooth.

Still to be done:
--Clean up wiring
--Figure out what to do about Motronic heater wires (cut or add a resistor)
--Try many more combinations of Closed Loop AFR settings
--Carefully monitor Motronic operation with GS-911 (no error codes so far)
--Get an exhaust gas analysis after settling on an AFR.

I'm not sure how much I can get done before the snow starts here in MA. When it does start snowing, the bike will get opened up for a spline lube.
 

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Over the last two days I've put a few hours on the bike. I have to say, that the slight downward shift of Closed Loop Lambda (AFR) from 1.000 to 0.965, has made a remarkable change in smoothness and low-end power. There has not been any sense of hesitation, in fact quite the opposite. I'm now running RPMs between 2500 and 3500 around town, even in 5th gear.

As far as the Motronic ECU is concerned the data looks like this:

Total data points: 4,000
Percent Closed Loop: 45% (same as before for the local conditions)
Average Closed Loop Lambda Voltage: 410 mV (right where expected, indicating good loop closing)

The new shift plots are looking the same as the earlier stock sensor plots. The big difference being the improved performance and the AFR meter reading 14.2:1 +/-. The above also indicates that the Motronic has been "convinced" to accept the programmable O2 setting and doesn't know that I've richened Closed Loop Lambda.

The next tests will be on the highway.

There are several variables still to be tuned:

High Lambda Voltage: (800 mV to 1V)
Low Lambda Voltage: (0V to 200mV)
Low Lambda Value: (how far below the 0.965 mid-point)
High Lambda Value: (how much above the 0.965 mid-point)
Target Lambda: (is there a better target that 0.965, implied AFR 14.2)

Filter Sensor inputs?
Monitor Sensor waveform.

In spite of what needs to be evaluated still, it looks to me like a slightly lower Lambda target (richer AFR) makes a MUCH smoother bike.

Will post up some charts later.
 
Data Plots from AFR 14.2

Here are some plots of several thousand data points acquired while running at 14.2 Air Fuel Ratio (AFR). The key observation is that the Motronic is operating normally, unaware that it has been spoofed to run at Lambda=0.965 which is an equivalent gasoline AFR of 14.2.

This an acceleration through a couple of gears with a warm engine. Notice that just like the earlier chart (a few posts back), the Motronic goes into closed loop while the RPM is accelerating. The Motronic doesn't know the Closed Loop AFR is 14.2, but for the rider (me) the engine feels much stronger and smoother because the AFR is richer.

14.2lrpm.jpg



The next two charts show a before (14.7 AFR with Stock Narrow Band O2 Sensor) and after (14.2 AFR with Wideband O2 Sensor and LC-1 connected to the Motronic in place of the Stock Sensor). Although the shapes of the curves are different due to how I have set up the hi/low transitions (something I will continue to experiment with) the key takeaway is that the Mean (average) and Median voltages are nearly identical (about 20 mV different). This suggests that the Motronic is controlling Closed Loop operation and is satisfied that it is in charge, producing the same average Lambda in Closed Loop.

Stock O2 Sensor
14.7closedlooplambdav.jpg


Wideband O2 Sensor
14.2closedlooplambdav.jpg


Next I will get some highway riding time in.
 
For those interested in the most arcane aspects of this project (probably no one but me ;) ), might like to try it or who might offer some insight:

--Both the heater and the sensor are isolated from the case (meaning they are not grounded to the exhaust) in this four wire O2 probe.

--The wire called signal ground seems to have a 100 ohm source impedance (more to be confirmed), and the open circuit voltage is 140 mV. Since the sensor is isolated from the case, this strongly suggests that the entire sensor signal is offset by 140 mV. I have read that the reason for this offset is to allow shorted and open leads to be detected by the ECU--makes sense. Right now I may have the +Signal going negative relative to the -Signal.

--I have also read that the ECU builds closed loop adaption tables so I should be doing a full reset of the ECU each time I change an LC-1 parameter.

--This signal + side seems, from research, to be routed to a dual comparator circuit that creates a +/- 25mV hysteresis window.

Although things are working really well, I am not convinced I am getting a good rich/lean toggle yet so I will probably go and get an oscilloscope so that I can look into all this with a bit more certainty.
 
Hello Roger,
WOW, you sound like you're as bored as I am.:blush

Hey Red100RT,

Yeah bored and intrigued at the same time ... a bit more ...

It turns out that the sensor does float on a signal 140 mV above ground. Any O2 sims like mine have to add this to the lc-1 or other o2 computer. Although I'm still fine tuning, the bike is running strongly at 14.2:1 (13.7 to 14.7) Closed Loop. Will continue to report the clean-up work. The challenge is getting two sensitive computers, motronic and lc-1 to each love the new environment and for the motronic to be blind to it. I expect to refine:

--Wiring length
--Component positions
--Motronic heater emulation
--Electrical noise
--Simulated o2 rise time.

In spite of these planned improvements the bike continues to be smooth and powerful through all gears over a much wider RPM range.
Roger
 
Hi Roger,
If I understand you correctly the open loop state results in a fuel air mixture ratio of 14.2 to 1 from a closed loop ratio of 14.7 to 1, correct?
 
Hi Roger,
If I understand you correctly the open loop state results in a fuel air mixture ratio of 14.2 to 1 from a closed loop ratio of 14.7 to 1, correct?

My project is focused on Closed Loop operation. The normal target in closed loop operation is 14.7:1 with the mixture toggling once a second (approx.) from about 14.2 to 15.1 or so.

What I have done is move to a Closed Loop target of 14.2:1, varying from about 13.7:1 to 14.7:1 at the same once per second rate (approx.).

Even that small shift (about 3% richer) in Closed Loop range has made a significant difference in performance. It may also be that my old O2 sensor had a characteristic that made it a few percent leaner than normal, I don't know yet. Still, just a bit richer and it's a lot better. Although I never noticed a bad surge, my bike just felt "held back" once it warmed up. It's possible that other 1100 and 1150s with more pronounced surginess would get more benefit.

For Open Loop, in order to deal with the fact that E10 gasoline is 4% leaner than pure gasoline, I have installed a BoosterPlug, which delivers a richer mixture by about 6%, a good offset to the E10. The BoosterPlug does not affect the Closed Loop operation which is governed by the O2 sensor.
 
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Roger,

I suspect that, over time, your Booster Plug may become redundant. As you put more and more time on your bike with a closed loop target of 14.2 to 1, the ECU will accumulate adaptation values that it then applies to open loop operation (often referred to as Long Term Fuel trim).
 
Roger, repeat after me: T-E-C-H-L-U-S-I-O-N

Not trying to be a smart a__ but with your LM1 you could probably install a techlusion and adjust the mixture to the ratio you seek while keeping all else stock as this device works with the stock O2 sensor in the circuit. Would be interesting to see what results you get.
 
Roger, repeat after me: T-E-C-H-L-U-S-I-O-N

Not trying to be a smart a__ but with your LM1 you could probably install a techlusion and adjust the mixture to the ratio you seek while keeping all else stock as this device works with the stock O2 sensor in the circuit. Would be interesting to see what results you get.

Thanks for the suggestion but did look it over pretty carefully. Unless the Gen 4 device is now available for the R1150, the earlier products don't affect Closed Loop operation.

When I go to their web site and On-Line store, this is the model they offer: FI-1031. It can affect Open Loop but not Closed Loop. During cruise and acceleration, the R1150 is often in Closed Loop mode, hence its issues.

Also, I wanted the least invasive solution to Closed Loop richening. The Techlusion Gen 4 (if available) required intercepting the injector signals. The PowerCommander III has a Wideband O2 but again intercepts the TPS and Injector Signals.

By only modifying the O2 Sensor path, I'm letting the Motronic do what it was designed to do, just shifting the O2 switching point down a little.

Happy Holidays
 
Open Loop AFR Results

Today I got a chance to pull the fairings, lift the tank and disconnect the O2 Sensor input to the Motronic. My goal was to see what the Open Loop Air Fuel Ratios (AFR) for the Motronic 2.4 looked like.

As a reminder, I have a Wideband LC-1 installed in place of the normal Narrowband O2 sensor. Usually it is set to 14.2:1, so when the motorcycle goes closed loop, I can't tell what the Motronic would do on its own, with the O2 Sensor disconnected.

I also pulled the Pink CAT Code Plug and looked at those results as well.

Procedure:
1) Disconnect Motronic O2 Sensor
2) Disconnect BoosterPlug
3) Reset Motronic by pulling Fuse 5, etc.

Results:
From Cold Engine (40F) to Warm Engine (140F-ish): AFR Range 13:1 to 14.7:1
Warm Engine Cruise (3rd, 4th, 5th gears; 3000 to 5000 RPM): AFR Range 14.5:1 to 15.2:1

Comments: There was no sign of a rich Limp Home Mode. Without O2 Sensor connected, mixtures got leaner than 14.7:1.

Next Test:
1)Pulled Pink CAT Code Plug
2)No BoosterPlug
3)O2 Sensor Disconnected
4)Motronic Reset

Results:
Warm Engine Cruise (3rd, 4th, 5th gears; 3000 to 5000 RPM): AFR Range 14.7:1 to 15.5:1.

Comments: Pulling the Pink CAT Code plug definitely created leaner mixtures than with it in, by an amount I would guess was about 0.4 AFR leaner. I would not ride without Pink CAT Code plug installed.

Summary:
It looks to me like the stock fuel tables in the cruise range for the Motronic MA 2.4 are centered around 14.7:1 and get leaner somewhere between 2,500 and 4,000 RPM depending on TPS. I often saw AFR readings in the low 15s.

It may be that without the O2 sensor installed, and with the E10 Premium fuel I'm running, the Motronic stock fuel tables result in leaner than 14.7:1.

As you can guess, I will be reconnecting the LC-1, reprogramming my Closed Loop O2 to 14:2:1 and reconnecting the BoosterPlug for Open Loop enrichment.

PS: I broke a tab on one of the fairings in my rush to open the bike. Any suggestions for how to glue to reattach a piece to the fairing (in the cylinder head area)?
 
Open Loop AFRs with Boosterplug

Ran the same Open Loop tests with the BoosterPlug installed, as expected, about a 6% richer mixture across the board.

Procedure:
1) Disconnect Motronic O2 Sensor
2) Connect BoosterPlug
3) Reset Motronic by pulling Fuse 5, etc.

Results:
Warm Engine Cruise (3rd, 4th, 5th gears; 3000 to 5000 RPM): AFR Range 13.5:1 to 14.5:1

Open Loop, with the BoosterPlug installed, the motorcycle seemed to run strong in all gears and modes (accel, cruise, decel), much better behaved than with stock Narrowband O2.
 
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