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Introduction and O2 Question


roger 04 rt

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Changing the subject back to my Wideband and O2 research, I've been looking at the signals going to and from the O2 sensor.

 

This is just some, "isn't that interesting" stuff. The stock O2 sensor is two devices in the same package. One device is a heater to make sure the second device, a lambda cell, is hot enough to function properly.

 

Stock O2 Sensor Heater

—On the R1100 and R1150, +12V to the heater in the O2 sensor comes from the same circuit that powers the fuel pump and fuel injectors.

 

—The ground connection for the O2 heater is hardwired to ground on the R1100 so the heater comes on as soon as the engine starts.

 

—On the R1150 the "ground" wire for the heater is connected to a switch in the Motronic that waits the motor to be running for a minute or two before it turns the heater on. I can only guess why. It may be for reliability—heater is off till it is warmed by the exhaust so the heater isn't cold shocked at startup.

 

—A malfunctioning heater could keep the sensor from working well. In my test setup I keep an LED connected to the heater so I know if it's on.

 

Stock O2 Sensor Lambda Cell

When hot (750F or more for a workable signal) this cell puts out about 800 mV when there is no oxygen in the exhaust (mixture richer than 14.7:1). When it detects any oxygen in the exhaust, mixture leaner than 14.7:1, it outputs only 100mV. So the O2 sensor only tells the Motronic if the exhaust gas has, or does not have any oxygen in it

 

—On the R1100, the low side of the lambda sensor is connected to ground. The high side connects to the Motronic.

 

—On the R1150 (and 1200s too) both the high and low wires connect to the Motronic. There is no direct connection to ground. Inside the Motronic is a very clever circuit that "adapts" to the signal swing. Even if the lambda sensor isn't working well the Motronic manages to find the 14.7:1 changeover point. I've cut the signal by 2/3 and the Motronic MA 2.4 manages to find a workable signal.

 

—I'm wondering how many 10-20 year old lambda sensors are still functioning properly. It really is a part of the bike that we're blind to. And to make matters worse, not only Re we blind to what it's doing, it is the Motronic most important sensor for good running qualities. If its bad you'll run badly.

 

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Morning Roger

 

On the 1150 holding the 02 heater ground until the engine has been running for a short while I can only guess.

I don't believe it is for 02 protection as most older narrow band automobiles brought the 02 heater on as soon as engine starts. Also the 1100 brought the (basically same) 02 on as soon as engine started & those 02 sensors are hearty as paper clips.

 

The thing that comes to mind here (just a guess though) is the 1100 had a stalling issue (in stock unmolested form) under some slow cold ride off conditions just about the time the 02 sensor started reacting. That problem usually went away if the 02 was disconnected. If the 02 operation could be delayed until the engine was a just bit warmer that stalling issue might be prevented.

 

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I don't have the data yet but I'll bet that the heater is triggered by the oil temp sensor. One thing I know is that the heater comes on minutes before closed loop starts. The LC-1 install wants the sensor mounted betwee 10 and 2 o'clock so that condensation doesn't build up. Come to think of it there is extra spark advance during the time when the heater is off. I don't know if the extra advance termination and heater on are coincident but I'll check.

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Here's an update on the LC-1 on my 2001 R1150 GS:

 

The fuel injectors I had sent off for cleaning (RC Engineering) came back today. The report showed they had flow rates of 315 and 294 cc/min before cleaning; and 321 and 319 cc/min respectively after cleaning. The 21 cc/min difference between cylinders before cleaning seems like a lot, which I believe could account for the slight surge I still had after installing the RC-1.

 

So I installed the cleaned injectors and went for a ride, syncing the TBs after the engine was fully warmed up. The surging is now gone! I had forgotten just how smooth and torquey the GS is with the richer fueling. The LC-1 transformed the bike. I rode like a hooligan coming home – big smile on my face, 30 degree weather notwithstanding.

 

Thanks Roger for your help every step of the way. For me, this is a modification well worth doing.

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Well, going to take my first ride with the LC-1 tomorrow or Friday, can't wait! If I pull a wheelie with my RT...... :rofl:

 

My '04 RT doesn't pull wheelies, at least I can't make that happen ...

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It won't happen using just the gas, you need the clutch too :D

 

Dan.

 

Mine does not need the clutch, roll in 1st gear at about 20mph, dip the throttle then gas it with a tug on the bars...

 

Not a massive wheelie - just a few inches off the road...

 

Andy

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Here's an update on the LC-1 on my 2001 R1150 GS:

 

The fuel injectors I had sent off for cleaning (RC Engineering) came back today. The report showed they had flow rates of 315 and 294 cc/min before cleaning; and 321 and 319 cc/min respectively after cleaning. The 21 cc/min difference between cylinders before cleaning seems like a lot, which I believe could account for the slight surge I still had after installing the RC-1.

 

So I installed the cleaned injectors and went for a ride, syncing the TBs after the engine was fully warmed up. The surging is now gone! I had forgotten just how smooth and torquey the GS is with the richer fueling. The LC-1 transformed the bike. I rode like a hooligan coming home – big smile on my face, 30 degree weather notwithstanding.

 

Thanks Roger for your help every step of the way. For me, this is a modification well worth doing.

 

That is a fairly large injector mismatch for a lean-fueled engine as yours was with the stock O2 sensor installed. When using the stock sensor I see AFRs move between 14.3:1 and 15.1. Since your cylinders had a 7% fueling imbalance so taking half that amount and adding another 3.5% to the 15.1:1 your leanest cylinder was at times in the vicinity of 15.6:1, a very lean mixture.

 

Also, around stoic, the fuel is converted to power at about half the difference of 7%, so one cylinder was producing 3-4% more or less power than the other. Your engine should be somewhat smoother now.

 

As you richened the mixture with your LC-1 but before you cleaned the injectors, you adding fuel and consuming the excess oxygen. As you do that your bike became less sensitive to the injector imbalance because once you've consumed all the oxygen the excess fuel can't be burned and the power differences diminish.

 

Glad it is working out for you.

RB

Edited by roger 04 rt
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At long last the day finally came today to fire up the R1150RT (04) and go for a ride to test the LC-1 with wideband O2 sensor. I am running with 13.5:1 AFR dialed in on the LC-1 along with a 3.5 BAR fuel pressure regulator.

 

I did most of my run on I84 from Baker City to Ontario and back a distance of some 135 miles with some pretty good 6% grades. The temp was 45F sunny with calm wind.

 

After giving the Motronic time to "learn" I began doing some 6th gear roll ons allowing the revs to drop to 2500 then rolling on the throttle and all I can say is WOW!! It is like having a completely re-tunned motorcycle. I have always felt like I should be in 5th gear for most all of my riding on freeways as well as secondary roads but no more. She would pull effortlessly in 6th from 50 MPH right up to 100+ MPH and RIGHT NOW with no sensation of needing to be down shifted at all. In fact, I found myself having to really pay close attention to my speed because the motorcycle performs so smoothly and effortlessly. Also, it has never idled so smoothly, kind of reminded me of a multi cylinder auto engine. I makes these comments honestly without exaggeration, I hope.

 

Was installation of the LC-1 worth it? Not only yes but HELL YES! I would gladly pay double the price for this kind of performance.

 

Thanks Roger :):)

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Really glad to hear that it's working out.

 

Since this thread is very long now I'd like to mention that although I made several dozen tests to make sure that the LC-1 worked harmoniously with the Motronic, the installation is in most ways pretty easy. Anyone wishing to make this mod doesn't need to remake any of my tests.

 

If you get an O2 sensor connector, wire it per the diagram below and program 6 numbers with a PC, it will just work.

 

I would be happy to provide e-mail support this year for anyone who wants to give it a go. The outlay for all the parts is less than $200.

 

I know that this is not within everyone's skill set but the diagrams below are what needs to be done. Pull the various LC-1 cables into a plastic box and connect the wires.

RB

 

lc1.jpg

lc1wiringdiagram-001.jpg

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Hi James and Roger

 

This topic is always fun for me to look

 

This spring i will certainly buy a lc1 and install it. Presently, I have a homemade Booster plug and my O2 sensor is not connected

 

Here, there's about 3 ft of snow (for me it's white shit) so my bike will go outside at the end of april.

 

James, as you previously had a homemade BP, I would like to know if the 3.5 bar pressure regulator makes a big difference about the results you get. There's two things I would like to know.

 

1- If the wideband O2 can adjust the AFR to 13.5:1, why use more pressure if I can get the right AFR with only the Wideband O2

 

2- Is there a big difference to use the LC! with (A) a BP or (B) a 3.3 bar regulator

 

My main spark plugs readings always showed a coloration difference between the two cylinders so I will probably also do an injector cleaning.

 

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Hi James and Roger

 

This topic is always fun for me to look

 

This spring i will certainly buy a lc1 and install it. Presently, I have a homemade Booster plug and my O2 sensor is not connected

 

Here, there's about 3 ft of snow (for me it's white shit) so my bike will go outside at the end of april.

 

James, as you previously had a homemade BP, I would like to know if the 3.5 bar pressure regulator makes a big difference about the results you get. There's two things I would like to know.

 

1- If the wideband O2 can adjust the AFR to 13.5:1, why use more pressure if I can get the right AFR with only the Wideband O2

 

2- Is there a big difference to use the LC! with (A) a BP or (B) a 3.3 bar regulator

 

My main spark plugs readings always showed a coloration difference between the two cylinders so I will probably also do an injector cleaning.

 

Hi Legarem,

I use the 3.5 BAR regulator to richen things up when the bike is running in open loop and the O2 sensor is not providing feedback to the Motronic. You could accomplish the same thing by just using a BP without the 3.5 BAR regulator to richen in open loop. I found that with the 3.5 BAR it was not necessary to fudge the air input temperature. Before installing the LC-1 I ran with a homemade BP with O2 disconnected so the BP was always in the circuit. It always seemed like I couldn't really find a good value for the BP. It seemed like the bike was always running a bit too rich or lean and seldom just right. I haven't switched back and forth between the 3.5 BAR and the BP to compare because it is such a hassle to swap out the regulator and I would still use the regulator over the BP anyway. Roger totally convinced me with his extensive tests and data that the best solution was to not attempt to fool the Motronic or restrict its operation by disconnecting the O2 sensor and thereby preventing closed loop running.

 

Another interesting thing I observed the other day when I did my first test run with the LC-1 was how the bike started cold after not be started since installation of the LC-1 several months ago was the very quick start up. All I did was punch the start button and she started and ran like it was a summer day and already fully warmed up after a several hours run. The LC-1 in combination with the 3.5 BAR regulator simply transformed my motorcycle. Now my '04RT actually starts and runs better than my '94 R1100RSL, a complete reversal of what was. I said I wasn't going to fool with the 1100 but now.......

 

Oh, forgot to mention..I suspect that if the only mod to my bike was the LC-1 without the 3.5 BAR regulator or BP that I would be very satisfied with its performance. If I was going to try any further mod it would be to replace the regulator with the stock 3.0 BAR and stock AIT sensor.

Edited by JamesW
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The only reason to boost the fuel pressure or shift temperature down by 20C is to reduce the amount of time the Motronic spends adapting to the richer lambda. For example if you set the LC-1 to lambda = 0.94 (13.8:1) the Motronic has to learn (and fill in) a table of 6% correction values (Adaptation Values) since the basic tables have values (in the lambda control range) corresponding to 14.7:1 gasoline. That takes time for it to learn. And if your fuel has ethanol (4% leaner) it has to make a 10% Adaptation.

 

Also, the basic map has something like 12X16 values (192) whereas the adaptation table is perhaps 4X6, certainly much coarser. When you boost fuel pressure, you affect the amount of fuel injected by every one of the 12X16 values in the table. The boosterplug will do the same thing but no one knows if the Motronic puts any limits on temperature adjustments nor do we know if there are any affects on timing from the lower temperatures--none have been reported but it is an open question.

 

Hope that is clear.

RB

Edited by roger 04 rt
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Forgot to mention that i am going over to Big Twin at Boise this spring if they have another dyno day because I am very curious about how the torque curve has been affected by installation of the LC-1. This obvious torque increase at lower RPM which makes 6th gear so usable is just hard to describe in words. If there ever was a farkle worth purchasing it would be the LC-1 no doubt about it!

 

Now, I admit when this thread began I was very skeptical and even somewhat argumentative, but not anymore because I saw for myself and I just can't believe it!

 

Hope it warms up today as I feel the need to ride on my new '04RT.

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Thanks a lot guys

 

As my shed is not heated, in about one month (I hope) I will have to renew the gas hoses in the tank and the fuel filter, I will install the LC!,the regulator and makes the injector cleaned. I also have to replace the swing arm rear bearings for bushings. After that, my bike should be ok for a lot of time.

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James

 

I know you're using a R1200xx fuel pressure regulator. I looked at R1200RT fuel regulators and saw that there's a 3.5 bar regulator and after 2010 they used a 4 bar fuel regulator, Which one do you use ?

 

If I use a BMW part, do I have to change the fuel regulator housing or just the clipped fuel regulator that goes in the housing ? I would be happy to keep my hoses as stock as possible.

 

Thanks

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I'm sure Jim will comment but he and wsg used the 3.5 bar regulator, and just replaced it. There are two O-rings that may need replacement.

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Roger is correct, am using the 3.5 BAR regulator and it seems to be a good choice with the LC-1. In fact if I had it to do over I would just install an LC-1 and maybe think about the fuel pressure regulator. But the LC-1 for sure without any doubt.

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Just to be sure they are the right kits before ordering.

 

Are they ok ?

 

Did you buy one with a meter or not ? For the price difference, i'm tempted to buy the kit with the meter. Thanks

 

 

http://www.ebay.com/itm/Innovate-Motorsports-Wideband-LC1-O2-Kit-Air-Fuel-3769-/350710232730?pt=Motors_Automotive_Tools&hash=item51a7f5769a&vxp=mtr

 

http://www.ebay.com/itm/Innovate-3795-Motorsports-LC-1-Blue-DB-Gauge-Kit-Wide-Band-/151001014652?pt=Motors_Automotive_Tools&hash=item23285ca17c&vxp=mtr

 

Edited by legarem
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Either of these will work. A gauge is a "nice to have" but you don't have to have it. I didn't permanently mount the gauge but I think some will want to.

 

Over the long run, buying a serial to usb cable which you will need in order to set 4-6 simple parameters, will give you a gauge on your PC and a graph of AFR which is much more revealing—and a super diagnostic tool. Never again will you have to guess is my engine running rich or lean.

Edited by roger 04 rt
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Thanks Roger

 

Item with meter bought. For an added amount of only $15, I decided to take it with the meter.

 

Now I have to wait warm days to install it and test it at the end of april to feel the results.

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roger 04 rt

A couple of months ago I installed a second bung in the exhaust of my R1150RT. I wanted to have both a Wideband O2 and a Narrowband O2 installed and running at the same time. The idea was to let the Motronic use the Narrowband in the usual way while I recorded the results of Motronic/Narrowband by monitoring the Wideband. In other words using the Wideband to spy on the Narrowband. Second Bung Install.

 

The Wideband showed that the Narrowband/Motronic pair kept the Closed Loop fuel right at lambda=1 (AFR 14.7:1).

 

Then I wanted to see if there was some kind of circuit that could be inserted in series with the Narrowband to richen the mixture without having to add an LC-1. The Narrowband sensor is well designed and has a big change of voltage right at Lambda=1. Just a bit leaner and its output drops to 100mV. Just a bit richer and its output jumps to 800mV.

 

The exact rich output voltage increases from about 700mV at 14.6:1 to about 900mV at 13.8:1. That is a small voltage change for a large mixture change, which means it is too small a change for the Motronic to work with.

 

Compounding matters, in the rich zone, from 700 to 900mV, the voltage changes as the exhaust gets hotter from higher engine load. Another way to say the same thing is that the voltage that corresponds, for example, to 14.1:1 (slightly rich) changes with engine loading. Compounding the problem further, the Motronic has a clever circuit that figures out if the voltages have been shifted. It uses that circuit to ignore simple shifts of the O2 signal.

 

I also built a test harness which allowed me to add circuits in series with the the stock O2. I tried a dozen different ideas, including some patented circuits from nightrider.com that work on Harley Davidsons. Nothing worked.

 

Over the last year, I've gotten to know the owner of nightrider, Steve Mullen. One of his Harley O2 richening products has a microprocessor inside. As designed for the Harleys, it didn't work either. But a couple weeks ago, we discussed and agreed on a different algorithm. Steve coded it up and sent me a new "chip" just for BMWs.

 

To make a long story short, the new "chip", with some other circuit changes, will pull the Narrowband sensor several percent into the rich zone. The way it works is that the microprocessor module measures the stock O2 sensor voltage, filters it to reduce noise, and then alters the voltage transfer function so that the signal it sends to the Motronic looks like a normal Narrowband sensor that is switching at a richer lambda (range is 0-6% richer).

 

As it is designed (proto with many extra wires, below) you unplug the stock O2 and plug this device between the two stock connectors. There is a ground wire to connect also. There is already power in the O2 sensor cable so no power connection or new fuse is required. The final product will be about 1/2" x 1" x 3" with two OEM connectors, plus one ground wire.

 

I have test ridden this circuit at 13.8, 14.1, 14.3 and 14.45 and will post some charts and other data tomorrow.

 

For those interested, PM me. We will build a couple of modules for pre-production trials for R1150XX with Motronic MA 2.4. Assuming everything works it will then go into production.

 

RB

 

Prototype test cable harness and small O2 processor device. Final product would be just the processor, two thin cables with OEM connectors and a ground wire—a simple plug 'n play solution.

 

bmwiedproto.JPG

Edited by roger 04 rt
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roger 04 rt
Any reason this wouldn't work on an 1100RT as well? Its Motronic is not as smart but you are spoofing the signal before it ever gets there. And it uses the same narrow band sensor setup.

 

Nice work BTW. Enjoyed following.

 

There's every reason to believe that the Lambda shift circuit (or an LC-1) would work just as well on an R1100. One the R1150 is off the ground one of two things needs to happen: a) find a source for the male and female O2 sensor connectors used on 1100s; or b) make it with a new OEM Narrowband O2 sensor.

 

If you know of a connector source that would speed things up.

RB

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roger 04 rt

Below is a plot of the O2 Circuit with Narrowband at the bottom of the chart, and an LC-1 at the top. The LC-1 is set to 13.8 (the red line) but it would have the same look at any programmed AFR. The thing that jumps out is how solidly the Motronic locks the LC-1 onto the target AFR.

 

In the bottom chart the O2 Circuit & Narrowband was set to 13.8:1. The result was 14.0:1 at hot idle (the red line) and 13.6 (the blue line) at 80MPH cruise. Different loads resulted in different Closed Loop AFRs. Interestingly higher loads lead to richer mixtures which isn't terrible—some might even say it's a good feature. (Hotter exhaust makes the O2 sensor produce a given voltage at a richer mixture.)

 

This means the spread was ±0.2 AFR between idle and 80 mph and that was with the narrowband pulled a long way off its design point. There are some additional data sets below the charts. (Note that the first few minutes is very rich. That's the Open Loop Cold-Start Fueling.)

 

lc1vsbmwied.jpg

 

After two more test rides, I have a good data base at three settings. Setting 5, 7 and 8 are actual and setting 6 is estimated but I will ride it later. The data look pretty good. The curves for the various settings all look like the one above. Here are the different results:

 

S8: 13.8 ±0.2 AFR

S7: 14.1 ±0.2

S6: 14.3 ±0.15 (estimated)

S5: 14.45 ±0.125

 

It is my opinion that most bikes will run great at setting 6 or 7. An important point here is that when you richen closed loop AFR, the open loop fueling gets richer too, coming along for the ride through a process known as Adaptation.

 

As I said earlier, because of the heating, the mixtures get a little richer with higher loads. Looking at those numbers above, the lean end of the range occurs at idle and the rich end of the range happens at 80 mph.

 

There are still a few small adjustments to make to voltage levels and to the algorithm. Then we find sources for the OEM O2 connectors, then a few pre-production units.

 

RB

Edited by roger 04 rt
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roger 04 rt
Looks interesting. I wonder if that works on my 1100rt.

 

Dan.

 

Hi Dan, I haven't tried it on an R1100 but it should work. In order to make it plug 'n play for the R1100 there needs to be a source for the male and female O2 connectors (looking now) used on the O2 sensor. It could be made with crimp connectors and use the bike's existing O2 sensor cable/connector. RB

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roger 04 rt
The connectors on my bike are just like the ones in your pic above.

 

Dan.

 

Hi Dan,

I didn't know that I thought the r1100 used a different O2 connector. Can you tell me which years or models used which of the two styles below?

 

R1150

 

bosch-oxygen-sensor-bmw-r1150-k1200-oe-fit-function-f0b1.jpg

 

R1100 (I thought)

 

bosch-oxygen-sensor-bmw-r1100-k-oe-fit-function-bf5a.jpg

Edited by roger 04 rt
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Roger and others...

 

I noticed something interesting on my LC-1 equipped 2001 R1150GS. I have Lambda set at .94 (13.8:1 AFR). As long as I ride below 4000 rpms the engine hovers right around 13.8 on level going and modest uphills. However, above 4000 rpm the AFR goes up to 14.4 on level going while maintaining steady speed. If I increase throttle enough for the engine to pull a little, the AFR drops back to 13.8.

 

I've ridden several hundred miles, so I wouldn't think the Motronic is still learning. And even if it was, I would expect steady speed on level going to be running in closed loop, which should be 13.8. I've observed the above pattern in gears 1, 2 & 3. I'll need to get on a bigger highway to test it out in the upper gears.

 

Could it be that the Motronic is designed to lean out the mixture when it thinks the bike is cruising (steady throttle, above 4000 rpms)? I have no way of knowing for certain when the bike is in closed vs. open loop, since the only feedback I'm getting is the AFR gauge.

 

 

 

 

 

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roger 04 rt

Hi Wally,

I've noticed that on my bike, in neutral, Closed Loop stops just above 2000 RPM. Perhaps lighter loads exit CL earlier than I've seen.

 

This could be a difference between Closed and Open Loop areas for the RT and GS models. I can tell you for sure that my RT remains in Closed Loop up to something like 6000 RPM and at speeds over a hundred miles per hour. I've got lots of plots and data showing the Closed Loop status (GS-911) and AFR (from the LC-1).

 

Can you connect a PC and get a running log of the data. (I strap my PC to the rear seat). You run with the serial cable connected and a program you got with the LC-1 called Logworks. That will tell us a lot.

 

If you can, try running the same test with the Pink Coding plug instaleled (30-87-87a) we could figure out whether it is coding plug related, or whether the difference is my MA 2.4; or whether it's something else.

 

 

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roger 04 rt

Wally,

This is very very interesting data. I hope that you can do some logging.

 

It now seems to me that the Motronic might be executing a Deceleration Enleanment program in Open Loop. If that's the case, we'll need some more data to figure it out. That 14.4 is 6% leaner than your target AFR. If you had a narrowband sensor it would be 15.3:1 or leaner!

 

It is tempting to think about what it would feel like if under these conditions the Motronic was going back and forth between Closed Loop and Decel enleanment. Or what it might feel like if your bike was not running 13.8:1 but 14.7. Might it feel like sur.....

 

Okay, well let us know when you have more data.

RB

Edited by roger 04 rt
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roger 04 rt
Roger and others...

 

I noticed something interesting on my LC-1 equipped 2001 R1150GS. I have Lambda set at .94 (13.8:1 AFR). As long as I ride below 4000 rpms the engine hovers right around 13.8 on level going and modest uphills. However, above 4000 rpm the AFR goes up to 14.4 on level going while maintaining steady speed. If I increase throttle enough for the engine to pull a little, the AFR drops back to 13.8.

 

I've ridden several hundred miles, so I wouldn't think the Motronic is still learning. And even if it was, I would expect steady speed on level going to be running in closed loop, which should be 13.8. I've observed the above pattern in gears 1, 2 & 3. I'll need to get on a bigger highway to test it out in the upper gears.

 

Could it be that the Motronic is designed to lean out the mixture when it thinks the bike is cruising (steady throttle, above 4000 rpms)? I have no way of knowing for certain when the bike is in closed vs. open loop, since the only feedback I'm getting is the AFR gauge.

 

 

Hi Wally, I went out and did some quick datalogging in first, second and third gear. The Motronic does go Open Loop at small TPS angles and RPMs above about 4K--but that's what your numbers 14.4 were saying.

 

If there is a slight acceleration my mixture at 4500 RPMs got richer than the closed loop target (acceleration enrichment) but with even the slightest deceleration in 3rd gear the mixture got slightly leaner (deceleration enleanment).

 

This provides a possible model for 4000-rpm-and-above, small-TPS-angle, driveability problems. The Motronic is a) Open Loop; b) in low gears with lots of deceleration/acceleration torque, and c) in some cases not too far from triggering the abruptness of Overrun Fuel Cutoff.

 

The interesting thing is that with my 13.8:1 Closed Loop AFRs I can see these effects in the data log but I don't experience the effect as a driveability problem. If I cut the mixture to stock 14.7:1 I can start to feel the effect as well as see it in the log.

 

BTW, since it was connected (testing proto 2 now) I made these runs using the prototype narrowband-shifting device I mentioned a few posts back. So it seems to be doing just as effective a job as the LC-1 (which I still prefer for datalogging).

Edited by roger 04 rt
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Roger, I was away for a few days but now back home, and as soon as the weather clears I'll get out for more runs and will log data using LogWorks3.

 

By "small-TPS-angle" do you mean small differences up or down from current speed? My experience was at steady throttle above 4000 rpm on level going the AFR would drop to 14.4, and I experienced just what you describe, as if the Motronic cut off the the fuel completely but then decided not to, all in a split second. Not a big "surge", but detectable. Below 4000 rpm when the AFR is at 13.8 at steady throttle I didn't notice the problem.

 

I'm relieved to know you observed the same pattern on your RT - it assures me I wasn't just imagining this! Any guesses about why the Motronic is programmed this way?

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roger 04 rt

By small TPS angles, I mean in absolute terms. I went back and looked, and in third gear at about 4500 RPMs the throttle is only open about 7.5 degrees, Overrun Cuttoff is only 5 degrees of throttle rotation below that. The other interesting note is that the injector duration is about equal to that at idle, only 2 mS, half of which is dead time.

 

I also looked through other data for the 3rd gear, 4500 RPM period. It was all open loop. And the injectors pulses started dropping in duration when I dropped the throttle from 8.32 degrees to 7.68 as reported by the motronic leading to injection times dropping from 2.3 mS to 2.18 then to 1.73 mS and the AFR going from slightly rich to slightly lean.

 

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I had a chance to get out yesterday afternoon for a brief ride on the Interstate where I could get the bike into the upper gears. In 4th, 5th and 6th above 4000 rpm the AFR never got above 13.8, unlike the lower gears.

 

Does anyone have an idea why the Motronic apparently goes open loop (AFR 14.4) above 4000 rpm in the lower gears, but not in the upper gears? AFR stays right around 13.8 at steady speed on level going all of the time except above 4000 rpm in 1st, 2nd & 3rd!

 

I did observe a couple of times at higher rpm in the lower gears yesterday when the AFR dropped down to 13.8, but didn't get enough riding in to be able to replicate the conditions.

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roger 04 rt

At 4000 rpm, small throttle angles, the 1150 appears to be open loop. In the higher gears because you're going faster, the engine has to produce more power and your throttle is more open. At higher throttle angles the Motronic applies closed loop control.

 

I've spoken to the guys at PC and asked them about the chart below which shows where they believe the Motronic is closed and open loop. According to them, it is their understanding of it but they can't say for certain that it is accurate. The dark area is closed loop and the white area is open loop.

 

Why BMW has designated the various areas open and closed is harder to work out but it is either because closed loop is unreliable at those RPMs and throttle angles, or because they always want either leaner or richer operating conditions that closed loop would allow.

 

Back when I began this project it was partly because when shifting up in the low gears, I experienced roughness when the engine was warmed up, right at the "top" of the shift. It now appears that this is an area of leaner open loop

 

pc1150map.jpg

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I just received my LC1 so I'll install it as soon as the temperature will be ok

 

Someone here has a scrap R1200RT which I could buy the fuel pressure regulator (3.5 bar) He also has injectors for sale. The 1200 injectors don't have the same part # as the 1150. I was asking myself if it could be a good thing to also try 1200 injectors. Physically, they appear to be the same.

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roger 04 rt

As long as the for part number is 13531465107, that will be good. I have found it difficult to compare injectors. For a while I tried to find some that had 10% more fuel flow. But I wanted: same exact physical size, same connector, same number of orifices, same spray pattern and angle and same impedance. I eventually gave up after many hours of web research and contacting suppliers.

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roger 04 rt

As I mentioned earlier in the thread, I've been experimenting with some options for shifting lambda. A fully programmable, accurate solution, with the ability to datalog, is a Wideband O2 Sensor with a Wideband Controller like the Innovate Motorsports LC-1. (As a note, there are other manufacturers of this kind of product: Zeitronix, PLX, & wbO2. Also, I'm still working on a device that can pull a Narrowband O2 Sensor several percent to the rich side (this is looking pretty good).

 

The other day, I had someone build me a Wideband O2 Sensor (Bosch LSU 4.2), with a fixed-AFR shift Wideband Controller built into the cable (photo below, small controller not shown). At the moment it's not quite compatible with the Motronic MA 2.4 and it ends up running 9% richer than stock when it is set to 6% richer--still looking into it.

 

What was interesting was at 13.4:1-ish my bike's hot idle had increased to 1400 RPM from about 1200. I also noticed on a local trip to the Post Office I was in a higher gear (6th) than usual (5th). Like everyone, I shift by feel and was quite surprised that I was going 48 MPH at 2400 RPM.

 

While it's probably too rich (?), it seems the 1150RT likes its fuel.

 

RB

 

13point8.JPG

Edited by roger 04 rt
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roger 04 rt

Narrowband O2 Closed Loop Shift, progress report.

 

Proto 2 of the Narrowband shifter seems pretty well set for the R1150 series. I have found an interim connector supplier at a too-high-price but it does allow me to have some preproduction units built. (Proto 2 Photo below, it needs to be prettied up with black cable, etc. Also, there is no exposed chip on the production unit).

 

For installation: the idea on the 1150 would be to pull the tank, connect the connectors in-line with the stock O2 sensor, run the grey cable along the right side, place the O2 circuit on the air filter cover, and attach a ground to the battery.

 

The specs look about like this:

(S1 means setting 1)

 

S1 14.7:1 (stock)

S6 14.35 ±0.15 AFR (2% richer)

S7 14.15 ±0.15 AFR (4%)

S8 13.8 ±0.2 AFR (6%)

(S9 13.55 ±0.25 AFR (8%) possible setting)

 

There are a lot of steps to get a product to production and to market but There are some resources to work those issues, can't say yet on timing.

 

bmw.ied.2.JPG

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I've been following (reading but understanding only about 25%) this thread from the start, but to be honest the science of it escapes me...

 

What is the 60 second pitch on what this product is and what advantages it will offer over a stock setup?

 

 

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roger 04 rt
I've been following (reading but understanding only about 25%) this thread from the start, but to be honest the science of it escapes me...

 

What is the 60 second pitch on what this product is and what advantages it will offer over a stock setup?

 

That's a very good question.

 

It adds a controlled amount of fuel (adjustable between 2-6%) to the entire fuel map of the motorcycle. It does this by slightly altering the reference point of the oxygen sensor. As you know, in a Closed Loop motorcycle like our Oilheads, the oxygen sensor is the final authority on fueling.

 

The stock sensor is set to an air-fuel ratio of 14.7:1, fairly lean. The advantage of a slightly richer mixture over stock is smoother engine operation between 2000-4000 RPM and a modest increase in torque between 2000-3000 RPM.

 

The reason it smooths the engine is that although we can balance air flow fairly well between the left and right sides, we can't balance fuel flow since that is set by the injectors. Adding a few percent to the fueling makes the motor much less sensitive to injector imbalances. And for reasons I don't fully know the answer to the R1150 just "likes" a little more fuel than the stock oxygen sensor mandates. Pilots would say the mixture is shifted toward the Best Power Mixture.

 

The Innovate Motorsports LC-1 is an excellent device for shifting the oxygen sensor and adding fuel. Those who have installed one say it has transformed the smoothness of their R1150. But the LC-1 is a project to install. The LC-1 is accurate and stable and outputs a data stream for diagnostics, whereas this device, which is based on the nightrider.com AF-XIED (but with a different software program, different electrical voltages and BMW OEM connectors) is easier to install.

 

There are other ways to add fuel like a Techlusion or Powercommander. They have to disable the oxygen sensor and tend to work in opposition to the Motronic. A shifted oxygen sensor works together with the Motronic to arrive at richer fueling by simply giving it a new, richer reference point.

 

Of course, as the fine print says, these devices are for off-road use only since they diminish the effectiveness of your catalytic converter, to the extent that 10 year-old cats do anything.

 

I hope this is clearer since I'll have to learn how to explain what it does more simply. I only intended to install the LC-1 for my own motorcycle but then saw some simpler possibilities that others might like to try.

Edited by roger 04 rt
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OK, i followed that enough to ask some follow-up questions.

 

- How would this unit affect MPG? (I'm cheap when it comes to gas, my cars get 45 and 48 MPG)

 

- What do you think this unit will sell for?

 

- Do you need a Beta Tester?

 

 

 

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roger 04 rt
OK, i followed that enough to ask some follow-up questions.

 

- How would this unit affect MPG? (I'm cheap when it comes to gas, my cars get 45 and 48 MPG)

 

- What do you think this unit will sell for?

 

- Do you need a Beta Tester?

 

 

 

--I believe that at a maximum, for each 2% you add to fuel, you will see a 1% reduction in gas mileage. So if you added 4%, you would at worst see 44.1 to 47 mpg. On my bike, with an LC-1 at 6% and a 21% fuel pressure increase, I got 50 MPG on the highway at a steady 60-65 MPH.

 

Typically, though I think it will be fuel neutral between 4-6% added fuel. The reason I believe this (and it will take many riders to know for sure) is that the low-rpm is improved enough that you will often ride in one higher gear. Not all the time, but often. This has been the experience of those who installed LC-1s.

 

Your mileage possibly could get worse if you up your "fun factor". It is so pleasing to crank on the throttle at 2500 RPM that you may just find yourself accelerating more often, until the novelty wears off.

 

--I'm talking with the manufacturing organization now and working out a price with them. I'm guessing around $150, perhaps a little more, depending how the discussions go.

 

--We're thinking of a pre-production run of 25 units. I think for the first 25 buyers I might offer some special terms and return rights.

 

This is all new to me. As I said, I didn't really plan to do this, just kind of fell into it.

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Roger Am anxiously waiting for your project to come to fruition. Years back I installed a Laser power chip, pulled my ccp and disconnected the O2 as per Lasers instructions. I did gain performance , but am now very curious with what you are doing as it works along with the motronic and not over rides it, if my understanding is correct. I really enjoy the tinkering, so I will gladly switch back to stock along with adding your enrichment prototype and comparing the difference. If there is a line when you roll out the first production parts , please put me close to the front!

Edited by taylor1
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