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roger 04 rt

Introduction and O2 Question

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roger 04 rt
Evening Roger

 

I don't know how the Motronic 2.4 does it but here are the basics on the Delphi system block learn & integrator from about that same era.

 

http://www.gnttype.org/techarea/faq/BLMINT.html

 

Thanks DR, for posting this ... again. I now remember that you posted this in a long forgotten thread I started called Long Term Trim ...

 

I reread it and although not a Motronic, it shows one way that the effect I've measured gets implemented.

 

I haven't mentioned it yet but lambda-shifting with a Wideband O2 as a strategy produces generally good results. However, it does have a couple problems in concept.

 

For instance, although cruise AFR seems too lean on the Oilheads (surging, leanness, straining at some RPMs, all due to the needs of the catalytic converter) it could be that WOT and warm-up enrichment is okay. When you lamda-shift, everything gets richer by the percent that you make lambda richer. In my case that's 6%. WOT has moved from roughly 12.8:1 to 12.1:1, and the cold-start enrichment is 6% richer too. During testing I've kept checking WOT and cold start. My bike still runs great but if I made cruise any richer I'd have WOT in the high 11s.

 

Using the PC III USB you can limit the WOT enrichment as I showed in an earlier table. Interestingly if you left the cells all at 0 on the PC III, then the Motronic would adapt everything up by 6%. By filling in the table as I showed with 6s except at 80 and 100% throttle, the Motronic doesn't have to do much adapting and WOT won't get too rich. Warm-up enrichment will climb though, that's unavoidable.

 

The warm-up problem could be negated by a second, capacitively coupled IAT sensor or by a switch but there hasn't been a need for that yet.

 

One other thing, its interesting to watch the AFR on a cold day on cold-start. The mixture looks ver lean for the first 10 seconds due to fuel condensing and not being burn. Then as it warms up, the mixture seems to be getting richer. Not more fuel, just more fuel getting burned in the cylinder and not condensed onto the engine components.

Edited by roger 04 rt

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roger 04 rt

I've been doing some more research on the Power Commander so I'd like to update the Notes section but can't go back to edit it. Here are the notes with updates, 5) and 6):

 

Notes

1) I am trying to get a PC III w/Wideband but have not run one yet.

2) The fuel table on the PC III allows you to enter percent increase/decrease. Typical injectors have a 1 mS dead (on/off time), I don't know if the dead time is taken into account by the PC III.

3) At 7250 RPM the injectors fire every 8.3 mS. The longest injection pulse that I've seen is 8.2 mS. This points out that you can't add 5% to the longest pulses with making them longer than the frequency of rotation in some cases. (However, the vast majority of the time injection pulses are less than 4 mS.)

4) I don't think there's a problem but I can't tell how the PC III responds to Overrun Fuel Cutoff when no pulses occur (i.e. the PC III isn't getting any engine speed info during that time.)

5) Because the Powercommander gets its +12V from the injectors/fuel pump and since the fuel pump goes off after a couple seconds, Dynojet recommends hitting the starter button before the fuel pump cycles off.

6) The Powercommander may not take injector dead-time into account (seeking clarification from Dynojet. If that is the case, I will update the sample fueling tables. For example, since there is 1 mS of dead-time in a 2mS injector pulse only a +3% is needed to get 6% enrichment.

Edited by roger 04 rt

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roger 04 rt
FF and MrC, FYI, here are a couple notes I add to the PC implementation:

 

5) Because the Powercommander gets its +12V from the injectors/fuel pump and since the fuel pump goes off after a couple seconds, Dynojet recommends hitting the starter button before the fuel pump cycles off.

6) The Powercommander DOES take injector dead-time into account.

 

In my case since I've boosted fuel pressure to shift the tables, the dead-time is automatically taken into account.

 

I just heard back from Dynojet. They do take dead-time into account within the PC III USB, they said. So no special provisions are needed and the tables would work as posted.

 

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roger 04 rt

With the help of a Mechanical Engineer in Greece who is running Alientech software to build his own fuel and spark tables, here is some spark data for the R1100GS. He and I have been going back and forth on some points and his software seems to misinterpret the axis for throttle/vacuum but it seems to match up with what I've measured.

 

Below, his table and my measurements.

 

r1100sparkfix.jpg

sparkadvancescatter.jpg

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roger 04 rt

An update and some new info:

 

Lately I've moved my Lambda setting from 0.94 to 0.92 which is another couple percent richer. I did this because I noticed that just as the bike was finishing warm-up (while riding) I liked the cruise performance just a bit better than once it went Closed Loop. The biggest difference between a minute before to after Closed Loop is a few percent more fuel. I'm not sure just where I'll stop adding fuel.

 

There are a couple IC engine performance curves I've found that you might find interesting. Although NOT specifically for an Oilhead, interesting nonetheless.The first is HP vs AFR at various power levels:

fig2-5.jpg

 

The second is flame front speed as a function of mixture (note that it is Fuel Air ratio not AFR). This shows pretty clearly that as you richen the mixture, you speed up combustion. It looks to me to be the equivalent of 2-3 degrees more advance for an AFR of 13.8 compared with 14.7, at 3000 RPM. At 6000 rpm it might be another 4-5 degrees if I'm doing the math right. Because of this effect I have been paying close attention to any hint of knock. There doesn't seem to be any probably because even though the timing advances some, knock resistance of richer mixtures is better.

 

ethanol-gasflamespeed.jpg

 

So the bottom line is that when you richen the mixture several percent you're probably getting a triple benefit: a bit more torque from the extra fuel, a bit more torque from the more advanced (relatively) timing, and better efficiency due to better running and therefore into higher gears a several hundred RPM sooner than at 14.7:1.

Edited by roger 04 rt

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roger 04 rt

As I mentioned earlier in the thread, I realized several months ago that a GS-911 can be used as a personal Dynomometer. The key things you have to know are the vehicle's weight including rider (~800 lbs.) and aerodynamics (Cd=0.66, Frontal Area 8 sq-ft), gear ratios, and rear tire diameter (25.59" for PR2 in motion). You log the GS-911 to a data file, import it into Excel, run some math on the numbers and you have Torque, Horsepower and Acceleration. Working out how many feet/second of velocity are created per RPM in a gear is tedious but not difficult (0.01956667 for 4th gear).

 

It has been my belief based on the feel of my 2004 R1150RT that it has gained torque in the lower RPMs from running Closed Loop at 13.5:1 and fuel pressure at 52 psi. Spend some time looking at the charts below. The Excel chart is a scatter plot of 6 test runs that I took in 4th gear, no wind, 3 in one direction on the highway, 3 in the opposite. Some runs were better than others but I used them all. There are significant torque gains below 3500 RPM, especially between 2000 and 2500--this tracks my driving experience. My RT produces about 55 lb-ft at 2500 RPM compared to 45 lb-ft on Ron's sample. Note: The numbers I measured are actually 5% higher but, as with a Dyno, I reduced them by a factor of 0.956 to account for weather conditions.

 

Between 3000 RPM and 5000, my bike accelerates at about 12 ft/s². Anything over 10 ft/s² gives you reasonable acceleration. In fourth gear that requires 48 lb-ft of engine torque, the curves on my RT show that at 2000 RPM. There are also gains at higher RPMs.

 

While I believe my data is accurate, the one thing I would say is that I was careful to get the run prepped for low RPMs by running along at idle in 4th or 5th gear, then crank open the throttle. I did not run quite to the Rev Limiter, choosing to let go of the throttle at around 7000 RPM. So my numbers might be a bit better due to the care of low RPM starting but I don't think that explains it all.

 

Enjoy the curve, I've got some more coming.

 

alltorque121112.jpg

 

Stock bike from Ron Hankison's web site.

 

http://www.r1150rts.com/DynoData/Dyno_004b.htm

Edited by roger 04 rt

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JamesW

Well, I took the plunge and installed an LC-1 on my '04 R1150RT. Installation was a snap in part thanks to Roger's excellent research and information. I borrowed a PC laptop to do the programming as I am a Mac user and the LC-1 software is not Mac compatible, wish it was. So, I went right for the gusto and programmed AFR to 13.5:1 and fired it up. Now, it is cold and snowing here today so I couldn't go for a ride but I can say the bike has never idled more smoothly. Was neat to watch it go closed loop with the display gauge showing 13.5:1 The idle was noticeably smoother than it was at the LC-1 default AFR of 14.7:1 Roger's thread convinced me that in the case of the Motronic 2.4 the only way to operate is with this wideband O2 sensor or just stick to the OEM narrow band sensor and put up with a bit of surging and never experience the performance these machines are capable of.

 

-Thanks Roger :)

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roger 04 rt

JamesW, Hope you get out to try the Wideband O2 before the spring. It has to stop snowing sometime. We're in a run of bad weather here too.

 

Being weather bound, I figured how to have excel create two scatter plots on the same chart. If you look back two posts the graph now shows Wideband and Stock Dyno runs. At some point I will program my own R1150RT to 14.7 and see now it "dynos".

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JamesW

Hi Roger,

That chart really makes me want to take a ride. The stock bike graph is pretty close to the dyno chart on my 1100. Hard to believe that much of an increase in torque. Yes, would be interesting to see what your own results would be at 14.7:1 Wish I had read a thread like this about 8 years ago. At least I got back half what I paid for a Techlusion when I sold it a couple years ago. No question in my mind the wideband is the way to go. More cost affective and easy to install and set up especially if you are a pc user, not so easy if you favor Apple. Just thought I'd throw that in. :)

 

 

Edited by JamesW

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roger 04 rt

I have Apples and PCs for just that reason.

 

Regarding the improved Torque, riding the bike is consistent with the improvement on the chart I've shown although I agree they are different bikes on different dynos.

 

I know my numbers are valid because I know the rate of acceleration (will plot soon), the weight of the bike and its resistance in the air. Even if you were to say that the torque numbers above 4000 RPM needed more analysis, riding my motorcyle makes it clear that the torque comparison at 4000 RPM and below is valid. I'll be interested to hear how yours rides when you get the weather. It's pouring here for the third day.

Edited by roger 04 rt

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roger 04 rt

In the interest of documenting what the Motronic does under various conditions, I've added a plot of fuel injection time and spark advance logged during the WOT runs I made to produce the torque curve posted above.

 

(Below the advance/injection plot I've added a summary of the GS-911 data log for anyone interested in what's being collected. A typical test run has several thousand lines of data that gets imported to an excel spreadsheet. The first two columns of time and RPM are used to calculate acceleration, and from that torque and HP.)

 

The conditions for the WOT runs were: shift the bike into fourth gear; running along at 1500 RPM; and then open the throttle fully until about 7000 RPM.

 

Looking at the plots below a couple things stand out. On the injection time plot you can see the Motronic fire off 7 mS shots of fuel right away to get the acceleration going—very rich, and keep in mind that each injector fires twice per combustion cycle. Then from 2200 to 4000 RPM, still WOT, the pulses drop to about 5.8 mS—still rich but a little less. From 4000 RPM to 5500 the injection time lengthens to 7.5 mS which is nearly on continuously at 7000 RPM. Between 5500 and 7000 RPM the engine is putting out 70 - 94 HP so the Motronic is keeping the mixture very rich. AFR on my bike is in the low to mid 12s for these WOT runs; by comparison the stock setting is in the 13s.

 

The Spark advance plot is interesting too. Although at mid RPM cruise the advance gets to about 43 degrees or so, you can see that the Motronic is more conservative with advance until 5500 RPM where for peak HP the Motronic brings in a few more degrees of advance to about 23.

 

wotinjectionspark.jpg

 

gs911data.jpg

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roger 04 rt
...

 

The Spark advance plot is interesting too. Although at mid RPM cruise the advance gets to about 43 degrees or so, you can see that the Motronic is more conservative with advance until 5500 RPM where for peak HP the Motronic brings in a few more degrees of advance to about 23.

 

...

 

Someone pointed out to me that this explanation is unclear. Nowhere on the spark advance plot does the advance get to 43 degrees. It probably should have read something like:

 

Looking at the Spark Advance plot, under the Wide Open Throttle conditions of this series of measurements, the Motronic is conservative with Spark Advance, holding it at 20 degrees or less until 5500 RPM. By comparison, under partial throttle cruising conditions the Spark Advance gets as high as 43 degrees.

 

In this forum, you've got to live with your mistakes unless you catch them quickly!

Edited by roger 04 rt

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JamesW

That sounds much better. I didn't say anything but thought 43 degrees advance was a bit much.

 

Thanks for the correction.

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roger 04 rt

A couple posts ago I showed the GS-911 data which is the source for the Dyno calculations that I've made. If you look at the first column there is a six digit number in milliseconds, and in the second column the RPM reported by the Motronic. By taking any two adjacent RPM differences and dividing it by the difference between the times for those two RPM values, you get a direct measure of acceleration. The formula for calculating the acceleration in feet per second-squared is:

 

Acceleration = (RPM2-RPM1)/(Time2-Time1)*19.6852 ... ( 19.6852 is equal to 1000 times the 4th gear drivetrain ratio including transmission, final drive and tire diameter)

 

In the chart below you can see the actual acceleration I measured for my R1150RT (the Blue Wideband line), five runs in fourth gear. These were 5 Wide Open Throttle runs after the Motronic had adapted itself fully to the Lambda = 0.92 setting (gasoline AFR 13.5:1). This acceleration data was the basis for the Torque curve I showed a few posts back. 12 feet per second-squared means the motorcycle accelerates by 8 MPH each second.

 

For the stock bike (Red line) I used the torque curves I showed earlier, and boosted them about 5% for the temperature and pressure conditions of the day; then calculated the acceleration that torque curve would produce in fourth gear. If you ignore the red (stock) line altogether, the Wideband acceleration is very good from 2000 RPM on up. And at 2400 RPM (11 fps2) the acceleration is nearly as good as at 5000 RPM (11.8 fps2). The boxer doesn't have to be a bike that only performs well at high RPMs.

 

Comparing the Red and Blue lines, there is a significant rate of acceleration advantage in favor of the Wideband curve between 2000 and 3000 RPM, which is what I experience while riding.

 

There's a saying, "There are three great lies ... lies, damned lies and statistics". That said, I'm pretty certain with all the measurements made and data collected, that the Oilheads run better with a bit more fuel. And given the number of comments you can find about bikes with Catalytic Converters running lean and the negative effects of that, it shouldn't be a surprise that a few percent more fuel improves them measureably.

 

allacceleration.jpg

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JamesW

Evening Roger,

Have you had a chance to test ride or experiment with a little richer mix around, say, 13:1? Have a copy of windows7 coming to install on my MacBook Pro so I will be ready to try some variations of AFR when weather improves.

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roger 04 rt

Hi JamesW, I've tried mixtures from Lambda = 0.92 to 1.06 (yup, 6% leaner than stock). Most of my riding has been at 0.94 (13.8 for gasoline) and 0.96 (14.1). Lately I went from 0.94 to 0.92 because I noticed that immediately before Closed Loop was still a bit better than Closed Loop--the difference being that pre-Closed Loop was a few percent richer.

 

Having run 0.92 (13.5:1) for a while now, warm-up is no longer better than Closed Loop so I think I've hit the point of diminishing returns.

 

Some other things happen as you reduce Lambda. First, cold-start and warm-up enrichments, which are a percentage below Closed Loop, also get richer--you could get too rich on Cold Start although I made a couple starts at 20F recently without problem. Second, WOT gets proportionally richer. I have seen WOT AFRs below 12:1 occasionally--plenty rich enough.

 

For these reasons, I will probably stay at 13.5 but in the spring I will likely try 14.1 (lambda=0.94) again.

 

Have you got out to ride yet?

RB

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JamesW

Nope, no riding. Nothing but cold (single digits at night) and snow/ice covered roads. Supposed to be cold and clear for next week or so but roads will be way to slick and then there is all the road sand. No salt just sand which is not the thing to be riding on. Probably will have to wait until March. :(

 

Thinking about moving to western Oregon, just rain there. :mad:

Edited by JamesW

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roger 04 rt

We finally got snowed in here too. I'm thinking of pulling the exhaust and having a second 02 sensor bung welded on so that I can see what the stock O2 sensor does. I've got an idea how to reduce the lambda of the stock sensor.

Edited by roger 04 rt

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JamesW

Now that would be interesting and the wideband would let you know how successful you are.

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roger 04 rt

That's the thought process. I'll have to do some hunting though to find a good neat welder in eastern Mass.

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JamesW

Just curious Roger but are you thinking about adding or inserting a DC bias voltage to skew the narrow band O2 sensor waveform as presented to the Motronic?

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roger 04 rt

Just curious Roger but are you thinking about adding or inserting a DC bias voltage to skew the narrow band O2 sensor waveform as presented to the Motronic?

 

Hi Jim, I'm analyzing 10,000 or so narrowband data points that I captured using the GS-911 before I mounted he Wideband O2 sensor. These points give me a good idea of the voltage range of the stock sensor in normal (14.7:1) open loop, closed loop and warm-up operation.

 

Although theory (and a lot of experience) suggest that there isn't enough useable AFR info at the rich end of of the narrowband curve, www.nightrider.com has a range of products that it (convincingly) claims will shift narrowband O2 sensors to 14.2:1. My experience with the LC-1 says that a lot of the richening benefit to driveability occurs at the 14.2 (lambda = 0.965) level.

 

What I'm not sure is whether there is any interest in a plug in adapter for the stock sensor. RB

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roger 04 rt

Replacing the stock narrowband O2 sensor with a Wideband O2 Sensor and Controller may be more of a project than many would undertake. The more I've worked with it the more comfortable I've become in saying that it's quite straightforward and without complication. It's also possible though that you could get a modest shift of Lambda with the stock narrowband sensor.

 

If you go back to page 1 of this thread you will find the chart that I'm reposting below. This is a plot of all the O2 sensor voltages that the GS-911 acquired during an extended test run. It is that known that something in the vicinity of 450 millivolts (0.45 on the chart) corresponds to a Lambda of 1 (meaning an AFR of 14.7:1). What is not so well documented is what is the AFR on an Oilhead when the O2 sensor voltage is between 650 and 900 millivolts. If the AFR is only 1% richer in that range then there's not much that can be done with the Narrowband sensor. However if those voltages correspond to a mixture that is 3-4% richer then there is probably a circuit and set of bias voltages that would allow a slightly richer operation of the Oilhead with the stock O2 sensor.

 

Since I'm planning to have the LC-1 initiate a recalibration of the Wideband Sensor (another neat thing about the Wideband O2), I'm thinking of putting my Narrowband in temporarily to see what the Motronic will do with a modified sensor. In other words will it hold Closed Loop if I alter the biases and voltages?

 

If that worked, then I might take my exhaust to a welder and have a second bung added so that I can accurately measure the Stock O2 sensor under standard and modified conditions.

 

If anyone knows of a good quality welder in the Metrowest Boston area I would gladly take the recommendation.

 

Stock O2 Sensor

14.7closedlooplambdav.jpg

 

 

 

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JamesW

My gosh, I would think in your area good stainless welders would be easy to find. How about the yellow pages under metal fabricator or machine shop?

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roger 04 rt

That helps, so I'm looking for a SS fabricator.

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roger 04 rt

AEM makes a No-Weld O2 Sensor bung that is a clamp with bung and strip of adhesive. I thought about it for a while and decided against it.

 

There are surprisingly few good spots on the R1150RT to mount a second bung but It looks like the weld-in bung will fit on top of the cat/muffler about a half inch back from the attachment clamp. I found a photo (below) that shows the stock O2 sensor mounted on the inner side of the feed tube to the cat. It appears that there's clearance if I mount the bung on top and near the front.

 

An advantage of that spot is that it will free-up about a foot of the wideband sensor's cable that is used now to reverse course and clear the transmission. A downside is that I think the sensor would need to be removed before removing the exhaust.

 

a20791812f79baa07da800_m.JPG

Edited by roger 04 rt

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JamesW

While you're at it you could live dangerously and take your grinder with a thin cut-off wheel and open the top of the cat chamber and cut out that offending piece of crap called the cat converter. Then you would have lots of places to mount a bung.

Of course you would still have to find a stainless welder but think how wonderous it would be to just get rid of that offensive mechanism. Nope, haven't been drinking.

 

Took the grinder to my '04 when it was but a youngster. :D

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roger 04 rt

I'm concerned that removing the cat material would alter the balance of the VE (fuel) table by changing the pressure at the exhaust outlet so I'll keep the Cat for the time being.

 

Here's where I'm thinking of mounting the bung and second sensor. If it works out, it might become the final home for the wideband.

 

exhaustphoto.JPG

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JamesW

That looks to be a good place and better than stock for sure and you could remove and replace much easier. Might be hard to remove exhaust assembly without first removing the O2 sensor but these are motorcycles not cars so nothing is easy due to compactness.

 

I don't think the cat converter is at all restrictive so about all you get with removal is a somewhat more mellow exhaust note. I wouldn't be concerned with changing back pressure. As I've said before the reason I opted to remove was the heat directly below the transmission but I really wonder if that's a valid issue. Guess I just had 50 bucks burning a hole in my pocket so I gave it to a welder. Guy did a neat job and you would never guess the catectomy was done. I do wonder how a richer mixture over time would affect free flow through the cat?

Edited by JamesW

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roger 04 rt

I've added a second O2 bung so that I can use the LC-1 Wideband sensor at the same time that the narrowband stock sensor is installed and feeding the Motronic.

 

The exhaust is back on with the Wideband sensor in the position near the catalytic converter, and the Narrowband sensor mounted in the new bung near the clamp. By connecting the Narrowband sensor to the Motronic and using the LC-1 as a recorder, I'm already getting data on the Narrowband/Motronic combo.

 

The first things that jump out at me:

 

—The stock Narrowband sensor is much slower than the Wideband, no question. That means the Motronic takes a lot longer to make corrections.

 

—The AFR spread is much larger with the Narrowband sensor. The larger spread plus the slower response shows fueling patterns that take seconds to change direction. Even in the quick data I've taken I've seen the mixture take 4 seconds to go from 15.4 to 14.2 while in closed loop. This is a long time and a fairly large change of mixture. The mixture change is large enough and slow enough that I'm sure it could be felt as su----g.

 

I'm going to do some riding with it tomorrow if the rain holds off and then post some plots and photos.

Edited by roger 04 rt

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JamesW

Well, that right there is reason to forget about using the narrow band sensor for anything but a bung hole plug. To do it right go to the wide band with LC-1. Somewhere I recall reading about slow response of the narrow band sensors. I think it was on some auto forum.

 

Windows7 on my MacBook Pro works great for making adjustments to my LC-1. Wasn't hard to install Windows7 in its own partition. The hard part was the time it took (6 hours) to download and install all the software updates. Made me appreciate the Mac OSX all the more. That said, I think when you marry the superior quality of Apple hardware with Windows you end up with a very fast and overall not bad computer system. Oops, forgot this is a mc forum, sorry.

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roger 04 rt

I picked up my exhaust Friday afternoon after a local welder with TIG capability cut a hole an inch and a half in front of the stock bung, and then welded in a stainless steel bung.

 

Next everything was put back together with the Wideband O2 in the usual bung and a stock Narrowband Bosch O2 in the new location. The Narrowband O2 got connected to the Motronic. In order to return the bike to stock operation the fuel pressure boosting regulator was removed from the fuel return line. While the Wideband O2 was removed from the exhaust and in free-air, the LC-1 was recalibrated—a nice feature it has.

 

Everything worked and the LC-1 and GS-911 started recording data on the stock setup. The LC-1 is a great tool for analyzing the stock sensor, coupled with the GS-911 you can clearly see what the engine is doing with mixture. Several test rides confirmed what I reported earlier, that the high/low AFR range during closed loop is between the low 14s:1 into fairly lean territory in the low 15s:1. Any injector mismatch would widen the range. The average AFR in Closed Loop was 14.7:1 as expected.

 

My test rides yesterday did remind me how differently the R1150 runs on the Narrowband sensor. When fully warmed up, with a light load in 1st, 2nd or 3rd gear in the 3000 to 3500 RPM range the motor feels on the edge of stumbling. On a slight downward grade in those gears/RPMs I could feel a light surging. I also found that I was shifting at higher RPMs than with the Wideband connected to the Motronic. Later when I pulled into the garage after the rides I could "smell" a hot-exhaust odor.

 

The richer mixtures (13.8:1) I had been running with the Wideand O2 connected for most of the past year improved driveability, softened the response to throttle and added muscle between 2000 and 3500 RPM. The richer mixtures were also reducing exhaust temperature. When I have time I will try and measure the temperature difference Wideband vs the stock O2.

 

Over the next few days I plan to see if the Narrowband sensor can be nudged to several tenths richer AFR—with a first target of 14.2:1. I'll report how that goes.

 

RB

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wallyging

I’ve been following roger04rt’s posts on enriching oilhead fueling using the LC-1 by Innovate Motorsports, and I finally installed one on my 2001 R1150GS (72,000 miles). I also installed a 3.5 bar k-bike fuel regulator. On Roger’s advice I programmed the LC-1 at lambda .96, or 14.1:1 afr.

 

I took the bike out for several test rides of 30-40 miles, and monitored the AFR using the gauge included with the LC-1. Here are my seat-of-the-pants impressions. I don’t have the experience with engines running at different AFRs that Roger has, and I did not do any data logging, so these are my non-technical, subjective impressions.

 

The best way I can describe the engine is it just feels more “frisky” to me, as if it is breathing easier (or, more correctly, less starved for fuel). It definitely has better torque in the 2500-3500 rpm range, and the on/off throttle is less abrupt. The bike surges less, but that is not completely gone (more on that later).

 

The bike switched to closed loop right at 3 bars on the RID. Since the 3.5 bar regulator was already producing fueling equivalent to lambda .96 the bike ran at 14.1:1 in closed loop immediately. It looked like the open loop tables had pretty much adapted to the richer closed loop mixture after a half hour of varied riding.

The bike seems to run in closed loop more than open loop. Under steady throttle on the flat and up and down moderate hills it stays in open loop – 14.1:1. I was surprised to find that when slowing down (reduced but not closed throttle) the afr went richer (in the 13’s) rather than leaner. It only goes leaner under closed throttle.

 

My bike’s surging is most pronounced under steady throttle at 2500 – 3000 rpms in the lower gears, when the engine is transitioning from power to no power (fuel to no fuel) on a level road or very slight downhill. As noted above, the afr during these periods is actually richer than 14.1:1, which suggests the surging is not the result of an overly lean mixture. Rather, it seems to this non-techie guy that the “surging” is the result of the Motronic going from a somewhat abrupt power to no-power, rather than the mixture being so lean that any unevenness in the afr of the two cylinders produces uneven power. I rode an hour this afternoon with lambda .94 (afr 13.8:1) and there was no noticeable change in the surging.

 

I’d like to thank Roger for doing all of the research and experimentation, and so generously sharing it with us. Roger was also very helpful during installation and tuning of the LC-1.

 

It has been a fun project! It took me more than a few hours to figure out where to put the LC-1 and the junction box on the GS since it uses the under seat space differently than the RT, and then do the actual installation and wiring, not to mention installing the 3.5 bar fuel regulator. I’m happy I made the modification, however, and I’m looking forward to warmer weather and more experimentation with the LC-1.

 

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JamesW

Hello Wally,

Well, that makes two of us that have installed an LC-1 mainly, in my case, as a result of Roger's thread and his research. I have mine programmed for 13.5:1 but must wait for a spring melt to try it out but I can't wait! About all I can say is that my '04RT idles much smoother in closed loop at 13.5:1 than idle at 14.7:1 which is the default AFR with the LC-1 before any programming. I am also running with the 3.5 BAR regulator. Thanks for your post, I don't feel alone anymore. :wave:

 

Jim

Edited by JamesW

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roger 04 rt

Hey Wally, Thanks for the post. I've been curious to hear how it worked out. And yes it is in closed loop a lot, roughly 50% of the time.

 

If memory serves me correctly, the 1150GS is different in a number of ways:

 

--lower compression

--different intake tubes, exhaust, heads, cams

--different coding plug

--and yours is a single-spark model year

 

It'll be interesting to hear about your longer term experience.

 

RB

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JamesW

Hello again Wally. You mentioned your bike seemed less sensitive to throttle input after installing the LC-1. One thing I found that was helpful in reducing low RPM slow speed surge was increasing throttle cable slack. I loosened the cable adjusters on the TB's so that the twist grip had about a 1/4" of free travel before lifting the throttle butterfly valves. This made the throttle less sensitive to small movements of my wrist while riding on roads that are even very slightly rough or bumpy. Seemed to help. I made this small adjustment before I ever heard of the LC-1.

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wallyging

James, the less abrupt throttle on/off that I refer to is a positive -- the bike responds to throttle inputs just fine, but it is not as "jerky" as it was before the richer mixture with the LC-1.

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JamesW

Yeah, I got that Wally. I think I wasn't too clear. I refer to the jerkiness produced when trying to go from closed (no) throttle to slight throttle as in slowing down and needing to modulate the throttle slightly. This is where having some slack in the throttle cable comes into play. Probably not too helpful when riding along at constant speed in lower RPM ranges though.

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wallyging

Thanks, Jim. I think mine has very little slack, and I'll try it with a little more.

 

I'm really itchin' for some reprieve in the weather so I can play around more with different settings on the LC-1. I'm going to set it back to 14.7 for a while to let the Motronic correct for the increased fueling from the 3.5 bar regulator. Then I'll set it back to 14.1 or less, to which the Motronic should adapt quickly, so I can get a better A/B comparison.

 

 

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roger 04 rt

I've been studying the response of the Motronic to the standard Narrowband O2 sensor over the past couple weeks now that I can run two sensors at the same time.

 

It turns out that one of the Motronic's interesting characteristics is that it adapts to the O2 sensor voltage swing. That is, as the O2 sensor swing gets smaller, the switching threshold inside the Motronic gets lower. Also, the O2 inputs to the Motronic are, in electronics terms, floating. A result of these two issues is that the Motronic appears, incorrectly, to run closed loop a little leaner than lambda=1.

 

Looking at 1000 closed loop voltages, 55% of them are "lean" voltages and 45% are rich voltages. (The median narrowband sensor voltage in closed loop was 360 mV. To be at lambda=1 you would expect the median to be 450 mV.) This bias toward lean was a surprise, and one that I've triple checked. I have to look at it more but I'm inclined to think that the 1150, in closed loop, might be running about lambda=1.01/1.02 when it should actually be 1.00.

 

The second thing I can see is that the afr variation using the narrowband sensor is roughly twice as large compared to the LC-1 closed loop. So the narrowband AFR swing goes from 14.4:1 to 15.0:1 whereas the LC-1, when setmat lambda=1, is 14.5/6 to 14.8/9.

 

At least for now, it looks to me like a better A/B comparison would be to use 0.94 and 1.02/3.

 

 

Edited by roger 04 rt

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wallyging

Very interesting data, Roger. It's great to have you doing all of the research on this. When it warms up a little I'll set lambda to 1.02 for a while, then switch back to .94. That should make for quite a difference in performance, I suspect. It will be interesting to compare with your experience.

 

The GS is a little different beast than the RT, and mine does not have the dual plugs like your's, but I expect I'll see a similar difference in performance.

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wallyging

It warmed uo to 40 degrees today so I reset the Motronic, programmed the LC-1 to lambda 1.01, turned on the "choke", started the bike and let it warm up. I have the 3.5 bar fuel regulator installed, so the bike was running about 6% richer than stock during open loop. While the RID was still at 2 bars the Motronic went closed loop, and I noticed an immediate and marked reduction in rpm. At closed loop the afr was right at 14.7:1 or a little leaner. (I am monitoring afr on the gauge included with the LC-1.)

 

It was dark, so I didn't go for a ride, but I should be able to do that tomorrow. I'll be interested to see if I can replicate this evening's results, and I'll take careful note of actual afrs during warm-up and at the switch to closed loop.

 

 

 

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roger 04 rt

Glad to hear you're getting some rideable weather. We've had really cold mixed with snow and cold. May just catch a warm wave.

 

Your idle experiment matches mine. I incremented lambda in 0.01 steps from 0.92 to 1.02 while taking data on another idea. At the end I moved lambda back to 0.94 from 1.02 and the idle picked up 150 RPM.

 

Your work on the GS with its different gearing, intake tubes, cams, heads and compression will give everyone a good idea how this will work on the single spark GS. Thanks for the effort.

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wallyging

I took advantage of our 60 degree weather today and took the GS out for the afternoon to experiment with different lambdas.

 

Taking Roger's advice I first programmed the LC-1 to lambda = 1.04 to get the bike back to what stock would be with the original O2 narrow band sensor. The engine felt more anemic, and the surging returned in the 3000 – 5000 rpm range and was noticeable during most driving conditions except for WOT. It didn’t take me long to realize I didn’t want to keep it at 1.04.

 

Next I set lambda = .92, and that did away with most of the surging, although a minor amount of hunting was detectable in the range of 2500 – 3500 under ideal circumstances (steady throttle on level or slight downhill grade on smooth road).

 

I thought .92 might be a little too rich for the cat and for mileage so I bumped it up to lambda = .94 to see if I could tell much difference. I couldn’t. The bike runs much better at .94 than it did at 1.04 – I guess that is not much of a surprise. But it definitely is more lively – I had to watch it to keep the front wheel on the ground in 1st and 2nd gear!

 

The Motronic adapted to the new lambda values quite rapidly. Closed loop adaptation was immediate, and open loop values seemed to change somewhat over the first 20 miles or so. It is difficult to tell what exactly what is happening just looking at the gauge.

 

I noticed a curious thing – when reducing the throttle, but not closing it completely, the bike ran richer. At a steady throttle on slight downhills the mixture would hold steady at the closed loop value, but if it was a steep downhill the mixture got richer – the Motronic wasn’t able to get back to the set lambda value. My only explanation is that the Motronic must not realize the bike is going downhill, and since the engine isn’t pulling as hard and not taking in as much air, the mixture becomes richer. I’ll be interested to hear other opinions on this.

 

Additional info: valves were adjusted within last 1000 miles, new plugs were installed, and the TB sync is spot on – verified again today. Could the bike possibly have dirty injectors (bike has 70,000 miles), or are GS’s more prone to surging?

 

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JamesW

Are you using the fabled Autolite 3923 plug by chance?

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wallyging

I had been using Bosch 4417's, but put in Autolite 3923's before going for a nice ride yesterday afternoon. I also put some Techron in the tank. Instead of focusing on how the engine was running I just decided to ride -- took some nice secondary roads, a few curves, a fair amount of hills, and 20 miles of freeway.

 

Boy what a difference compared to the "old" bike! There is a goodly increase in torque, particularly noticeable in the 3000-4000 rpm range where I often ride. I found myself giving it lots of throttle whenever there was the slightest opportunity, and had to be careful in 1st and 2nd gear not to let the front wheel come off the ground! I never had that "problem" before the LC-1. The "surge" seemed a little less than the day before, but I could still feel it. The wideband O2 modification is definitely a keeper. I'm running at lambda =.94 (13.8 AFR), and plan to just leave it there for a while.

 

A little reflection on my experience and exchanges with Roger leads me to wonder just what constitutes a surge? We talk about "surging" as though everyone knows what we mean, but I suspect it means somewhat different things to different people. Do conditions matter, for example, is it detectable in normal riding vs. optimal conditions for surging? Is there a way to quantify the surge -- how strongly it is felt, at what rpms, in what gears, etc.? Yesterday I could detect what to me was a slight surge, but I suspect others may not notice it or think of it surging. Since we use surging as one criterion of how our bikes are running it might be good to be more specific about what we mean.

 

 

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tallman

And, being redundant, 3-4krpm is where a lot of "hunting" happens.

Keep the revs higher and the bike runs better in almost every case.

YMMV

Not a criticism, ride your bike the way you want to but torque/hp/smiles happen higher up the rev curve on a boxer.

Best wishes.

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roger 04 rt
And, being redundant, 3-4krpm is where a lot of "hunting" happens.

Keep the revs higher and the bike runs better in almost every case.

YMMV

Not a criticism, ride your bike the way you want to but torque/hp/smiles happen higher up the rev curve on a boxer.

Best wishes.

 

You're right, that's the way the lean-fueled boxer performs. The point of adding some fuel by way of shifting Lambda, changes the game. Where the stock boxer appreciates higher RPMs, you can see from the chart below and others a couple pages back in the thread, that the well-fueled R1150 accelerates just as well (11 fpss) at 2300 RPM as the stock boxer does at 3800 RPM.

 

allacceleration.jpg

Edited by roger 04 rt

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tallman

Roger,

Yes.

 

But many/most will not go that route for whatever reason.

Hence, rev it and ride the boxer is good for them.

For anyone as informed and interested and willing to do the work/mods a different road.

 

Like I said, not criticizing.

 

Must have had hundreds of test rides with new to the boxer rider.

Too many wanted to ride it like a cruiser and park in the 2500-3k range in 5th/6th.

Their comments about the response/feeling etc would lead to another ride w/explicit shifting rev suggestions.

 

Most of them bought after that.

:thumbsup:

 

Appreciate all the time and work some of y'all do to explore the parameters.

Might even do that if I go back to a boxer.

Best wishes.

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roger 04 rt

Thanks tallman. I didn't take it critically but wallyging is the first to my knowledge to try this on the GS with single spark and lower compression, etc. He's getting the same low end boost that JamesW and I've reported on RTs. Interesting data point: when I switched back to the stock sensor I found myself shifting 800-1000 RPM higher than with the Wideband at 13.8. Like most, I shift by feel, not by the tach.

 

The question wallyging asked is interesting, what is surging and what is hunting, what are the exact processes happening? With that knowledge there might be a solution. Recently, with the stock sensor installed and connected to the Motronic but with the LC-1 and GS-911 recording, I was able to create the light-throttle, low-gear, slight-downhill symptoms (very subtle) wallyging mentioned but I couldn't see a pattern in any of the data. When I get time and interest I'll look some more.

 

 

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