ECU

[dlaing]

What doe 2% oxygen translate to in A/F ? 2/100 or a 1 part air and 50 parts fuel?

Or I guess we assume that the air is only 21% of our air, which is still a very rich 1 part air and 10 parts fuel....hmmm, oh I get it! It is the residue oxygen,

edit that should be 0.2%

 

So because it is measuring the residue oxygen and not the fuel and air going in, we are only guesstimating? or is there imperical evidence that there is a reliable correlation?

The CO vs. 02 Falco readings are not very comforting.

So to speculate, assuming our bikes are most efficient where they make the most torque, around 5000 to 6000 rpms, they would burn more of the oxygen at the proper fuel ratio than at maximum HP.

Following this logic, an 02 closed loop or a tuning link would falsely assume that at 5000rpm the bike needs more air than at 8000rpm (or below 4000rpm).

But maybe it is only a slight variation, or maybe the tuning link is smart enough to compensate.

Or maybe I am all wrong about efficiency???

The same might hold true with higher compression pistons resulting in a leaner map than desired.

 

moto, where were your futura co vs o2 differences?

[moto]

The conclusion I draw is that there was a fault at least in the exhaust system of one of the Futuras.

What do you think is the reason for this difference? When you have oxygen in the exhaust gas and everything else is ok the engine runs probably rather lean, or what am I missing?

What did the O2 sensor say at these two Futuras, in terms of Lambda or A/F?

 

40872[/snapback]

 

It was the same motorcycle. I just pulled up the charts and remembered that the measurements I was referring to were at two different spots before and after tuning, which is meaningful, but less so than if I refer to the same spot . As a for instance 62.73HP and 54.89Ft/Lbs of torque at 6K with 11.4% CO and 0.4% O2 at 100% throttle before tuning vs. 67.56HP and 59.08Ft/Lbs of torque at 6K with 4.7% CO and 0.2% O2 at 100% throttle after tuning. Another example, 99.48HP and 62.92Ft/Lbs of torque at 8.3K with 7.2% CO and 0.3% O2 at 100% throttle before tuning vs. 103.29HP and 65.26Ft/Lbs of torque at 8.3K with 3.2% CO and 0.2% O2 at 100% throttle after tuning. And another, 17.94HP and 39.99Ft/Lbs of torque at 2.3K with 12.6% CO and .2% O2 at 100% throttle before tuning vs. 18.76HP and 41.84Ft/Lbs of torque at 2.3K with 4.2% CO and 0.3% O2 at 100% throttle after tuning. I can find more examples at other throttle position/rpm combos and on other bikes if need be. The before tuning CO numbers do not indicate leanness and the pulse widths were shortened to achieve the improvements, which are as good as it gets, as the tuning was done up to the resolution of the equipment which is ± .1 to ±.2 HP. The EGA only gives percentage of oxygen, not "A/F ratio".

[Skeeve]

I have heard people say that regarding suspension, it is damping, not dampening, but I am not sure that is correct since dampen is what your shocks do.

40849[/snapback]

 

The only time *my* shocks "dampen" anything is when they're leaking!

 

The suspension dampers are there to damp out oscillations in the springs used to spread out the instantaneous loads over time. In this case, the usage is derived from terms like fire damp, ie: a non-combustible gas that puts out a fire. At no time is liquid of any sort implicated, which if present, would dampen the proceedings.

 

So there you have it! Now if I could just get people to start spelling "brakes" correctly...

[helicopterjim R.I.P.]

So there you have it! Now if I could just get people to start spelling "brakes" correctly...

40892[/snapback]

If it ain't broken don't fix it.

If it ain't brakin' - fix it!

[Guest ratchethack]

The only time *my* shocks "dampen" anything is when they're leaking! 

40892[/snapback]

 

So are you saying that if my shock were to break, it would lose it's damping due to fluid leakage, and that my brake could get dampened?

[Guest Pexi]

Okay, short term and long term trims ? If I interpret your mail correctly I think that you are referring to well developed automotive ECUs (maybe Alfa Romeo ?) that have the capability to "learn" and also to store what they have learned for future purposes.

 

You're 100% right . I know nothing about motorcycle ECUs , I've only played with Alfas and am now desperately trying to digest any information related to my Guzzi's electronical brains.

 

I do not know for sure, but I would speculate that those ECUs that are nowadays found in production motorcycles are not able to do this kind of long term learning. In other words, when ever you turn of the power, the ECU is left with the original base map. The base map will not evolve automatically over time.

 

That would explain why nobody has been talking about long term fuel trim here (except me, le monsier ignoranti)

 

Did this sound anything like what you meant ?

 

Yes, it did. Exactly.

[Cliff]

I think you guys are over complicating it with regards to gas analysis. Sure O2 is an indirect measurement and can be polluted by air leaks and even the valve overlap could cause air to pass straight from inlet to exhaust. The whole thing is like analysing a fractal image, always more detail the closer you look.

 

The important thing though is the bottom line and I will outline the results I have got on my two bikes.

 

With my sensor, if I set .6V as a target a short ride will give me a light grey coating on the sensor ( it shows better than the spark plug ). If I set .8V a short ride gives me a sooty black coating. Of coarse I can set any value in between and I expect a usable range of 0.5V to 0.9V. I couldn't tell you what the corresponding A/Fs are. I don't particuarly care. I can make and adjustment on the fly. Say changing the target voltage from 0.6 to 0.62. Doesn't sound like much does it but I will see my closed loop adjust mixture by a small percentage.

 

I find that the raw sensor voltage can vary substantially especially when tracking the leaner voltages. This is with static conditions - constant throttle, constant RPM, constant ECU output. Tracking to 0.6V I will see many "wild" excursions to 0V or .75V. I can understand that someone trying to be too smart and tracking it closely could get into trouble. I wont brag at being able to do something super smart that the OEMS can't do. I just did the simplest thing I could think of. Perhaps thats the secret. A good engineer will simplify, a team of engineers will complicate. The OEM ECUs have about 2-3 times more components than mine.

 

The raw sensor inputs are not the important thing, its the system's response to the inputsthat matters. Even with this seemingly erroneous data, I find that the tracking is stable. The closed loop adjustments will stay within 1% or 2% of the mean value.

 

Is 1-2% good?? I'll let someone else pursue that line.

[emry]

Well I don't even know where to start. At least this thread is in Technical Topics.

 

Lets not forget that O2 controls were only started as a response to government emission regulations and the use of catalytic converters. Early cat's needed all the help the could get!!

 

Maybe now that cat's are becoming more common place on motorcyles we will begin to see some better adaptive ECU's being used.

 

Pexi - Your post on the methods of Fi operation is great. That is in simple terms hows most modern "learning" automotive computers work. Where the LTFT can eventually completely change the base map dramaticly "Fuzzy Logic" (3+3+3=9 or 10 or 8 depending .....). This has some very good advanatges most notabily that the ECU can now adjust for the various runnning conditions but also normal wear and tear. I have even seem some cars have running problems after an engine replacement until the LTFT is cleared. Modern ECU's have gotten much much better, the refinement of resonable limits to the "fuzzy" and the better use of intelligent sensor sampling, (the ability of an ECU to ignore inputs that are to far from target) and "limp maps" have all made early FI problems obsolete.

 

Modern motorcycles have not yet begun to use the technology. I don't think cost is an resonable explaination, Honda and Kawasaki Heavy Industries both have extremely effective adaptive ECU's in wide spread use and have for some time. I believe it is more of an if it ain't broke don't fix it mentallity. The majority of motorcycle users in the world use them as short term, short distance, low milage vehicles. Long term adjustment just has not been a priority. The power to weight ratios of motorcycles make a seat of the pants fueling problems mostly unnoticable, particularly when we are talking in the 1 to 2 percent range. (But it is definately noticableto someone who knows how to read plugs.)

 

Personnally I would love to see closed loop on more motorcycles. It has really proven it's effectiveness in the automotive world, even if its primary focus has been to keep emissions in check. Careful programming could easily change that to best power.

 

As for the smapling of CO vs. O2. Moto did a good job of hitting that one, seems he has some gas analyzer experience. I think the ability of easily sampling CO is to expensive as compared to O2. My gas analzer cost me $6000. The last O2 sensor I put on my Toyota cost me $60. (It has three, 1 in each heder before the cat, and 1 after the cat. So the ECU can monitor the ability of the cats.) My 5 gas analyzer has about a 2 second delay for the CO results to be sampled and posted, but the O2 is almost in real time. Using O2 to react and produce electricity is very simple, CO is very expensive.

 

Heck that enough for now, the Porter (Sierra Neveda) is finally working.

[dlaing]

Heck that enough for now, the Porter (Sierra Neveda) is finally working.  

40931[/snapback]

Time to dampen our thirst, not our spirits, but with fine spirits!

It still seems to me that shocks dampen wheel motion:

 

dampen

 

v 1: smother or suppress; "Stifle your curiosity" [syn: stifle] [ant: stimulate] 2: make moist; "The dew moistened the meadows" [syn: moisten, wash] 3: deaden (a sound or noise), especially by wrapping [syn: muffle, mute, dull, damp, tone down] 4: reduce the amplitude (of oscillations or waves) 5: make vague or obscure or make (an image) less visible; "muffle the message" [syn: deaden, damp] 6: check; keep in check (a fire) 7: lessen in force or effect; "soften a shock"; "break a fall" [syn: damp, soften, weaken, break]

 

I have been visiting San Francisco this week. mmmmm went to a microbrew on Columbus called San Francisco Brewing company and had about the best American Stout ever yummmmmm.

Anchor on tap everywhere else...

PS anyone in SF have a silver V11S with Magni fairing, parked at Market and 2nd or 3rd....nice bike!

[moto]

I think you guys are over complicating it with regards to gas analysis. Sure O2 is an indirect measurement and can be polluted by air leaks and even the valve overlap could cause air to pass straight from inlet to exhaust. The whole thing is like analysing a fractal image, always more detail the closer you look.

 

The important thing though is the bottom line and I will outline the results I have got on my two bikes.

 

I find that the raw sensor voltage can vary substantially especially when tracking the leaner voltages. This is with static conditions - constant throttle, constant RPM, constant ECU output. Tracking to 0.6V I will see many "wild" excursions to 0V or .75V. I can understand that someone trying to be too smart and tracking it closely could get into trouble.

 

The raw sensor inputs are not the important thing,  its the system's response to the inputsthat matters. Even with this seemingly erroneous data, I find that the tracking is stable. The closed loop adjustments will stay within 1% or 2% of the mean value.

 

40907[/snapback]

I think I need to show another example from the Futura and come at this from another angle to further illustrate my point. For instance 53.92HP and 57.72Ft/Lbs of torque at 4.9K with 6.3% CO and 0.1% O2 at 89% throttle before tuning vs. 56.22HP and 60.22Ft/Lbs of torque at 4.9K with 3.4% CO and 4.0% O2 at 89% throttle after tuning. Another pull with the same after tuning settings yielded the same numbers exactly, but with the O2 content now at 2.4%. If one were to try to tune to O2 content, the target numbers would be in this range (after stagger and ignition issues were adressed): ~.3%-.4% (for large bores) 1%-1.1%(for small bores). You can see that if if the Futura had a closed loop ECU and tried to hit those targets, there would be a serious problem. How does the ECU decide not to respond to sensor inputs? Does it not respond if they are transient? I thought the whole advantage of using O2 was to be able to do just that. Does it not respond if they are outside of certain parameters? If so, it also won't respond when they are legitemately there.

[dlaing]

I put Moto's data into more of a chart form

 

HP RPM CO O2

62.7 6000 11.4 0.4

67.6 6000 4.7 0.2

 

99.5 8300 7.2 0.3

103.3 8300 3.2 0.2

 

17.9 2300 12.6 0.2

18.8 2300 4.2 0.3

 

53.9 4900 6.3 0.1 at 89% throttle

56.2 4900 3.4 4.0 at 100% throttle

56.2 4900 3.4 2.4 at 100% throttle

 

 

It looks to me as if one could aim for a 0.2 oxygen reading and get very good results.

The power would probably be just as optimal if one aimed for maybe a 4.0 CO

As for the inconsistencies that Moto saw,

perhaps Moto's tuner's oxygen sensor is not state of the art???

And perhaps many tuner's sensors are not state of the art?????

How do the Oxygen percentages match up to A:F ratio?

[Cliff]

How does the ECU decide not to respond to sensor inputs? Does it not respond if they are transient? I thought the whole advantage of using O2 was to be able to do just that. Does it not respond if they are outside of certain parameters? If so, it also won't respond when they are legitemately there.

40960[/snapback]

 

In my case I think it comes from mixture update rate and how I respond to the o2 inputs. My update rate is based on engine speed from about 1 per second at idle to about 10 per second at redline. Thats fairly slow in engine terms. There's also they way I respond to the o2 value. If I happen to sample in a transient and see 0V I don't go "give me full fuel Scotty". Instead I bump my mixture by 1%(my maximum increment). Chances are next time the sample is slightly over voltage and the mixture is pulled back again. If I happen to see 2 transients it will go another 1%. Chances of see 3 transients are fairly remote. Its a statistical averaging.

 

What tends to happen in practise is my mixture slowly fluctuates by about 1%. Of course this assumes the underlying map has been previously flattened. I consider that to be pretty tight. I think that equates to about a .1 change in A/F. So if my target voltage was set for 14to1 my engine running is between 13.9 and 14.1.

[Skeeve]

So are you saying that if my shock were to break, it would lose it's damping due to fluid leakage, and that my brake could get dampened?  

40897[/snapback]

 

Prezackly!

[moto]

I put Moto's data into more of a chart form

 

HP      RPM  CO  O2

62.7  6000  11.4  0.4

67.6  6000  4.7  0.2

 

99.5  8300  7.2  0.3

103.3 8300  3.2  0.2

 

17.9  2300  12.6  0.2

18.8  2300  4.2  0.3

 

53.9  4900  6.3  0.1 at 89% throttle

56.2  4900  3.4  4.0 at 100% throttle

56.2  4900  3.4  2.4 at 100% throttle

It looks to me as if one could aim for a 0.2 oxygen reading and get very good results.

The power would probably be just as optimal if one aimed for maybe a 4.0 CO

As for the inconsistencies that Moto saw,

perhaps Moto's tuner's oxygen sensor is not state of the art???

And perhaps many tuner's sensors are not state of the art?????

How do the Oxygen percentages match up to A:F ratio?

40969[/snapback]

I made an error on the second set of numbers I provided. They were all at 89% throttle.

 

Here are all of the readings for the rear cylinder on the Futura at 100% throttle after tuning pulsewidth to within ±.1 to ±.2 hp of best hp. I'm not going to post HC, CO2 or flux as they are not totally pertinent to the discussion (unless someone asks for them).

 

rpm ft/lbs hp CO O2

1904 15.97 43.91 4.2 0.5

2353 18.76 41.82 4.2 0.3

2655 24.75 48.90 4.2 0.3

3005 31.54 55.09 2.6 0.7

3306 36.13 57.39 3.3 0.7

3606 39.62 57.68 3.6 0.7

4004 44.01 57.68 3.7 0.8

4407 47.01 55.99 4.0 0.8

4906 55.59 59.48 2.7 1.0

5408 63.17 61.28 4.1 0.8

6007 67.56 59.08 4.7 0.2

6406 75.25 61.68 4.2 0.2

6810 85.08 65.66 3.8 0.4

7108 91.18 67.36 4.1 0.3

7408 95.49 67.66 5.1 0.2

7808 98.69 66.36 4.4 0.1

8309 103.29 65.26 3.2 0.2

8809 105.39 62.86 4.3 0.1

9309 107.60 60.70 3.4 0.3

9807 106.40 56.93 4.3 0.4

 

You can see that there are only four places out of 20 where .2% oxygen would have been an appropriate target. Then there's the 12.6% CO with .2% O2 example from before...

 

As far as my gas bench not being accurate, I use an Andros bench, which I definitely consider to be state of the art. See http://www.andros.com.

 

Again, I consider the correlation between "A/F Ratio" and O2 content to be tenuous at best, but I'm sure someone fom DynoJet could tell you how they consider them to relate.

[dlaing]

Could the O2 readings be wrong because you are not holding it the setting for a full 40 seconds?

http://www.andros.com/6800spec.htm

Or am I reading the specs wrong, and that

Also the O2 sensor is accurate + or - 0.1 % which is fine, but we should not be nitpicking between a 0.1 and a 0.3%...but then again, I'll bet that on a given day the accuracy is much greater.

the plus or minus point one probably is against a standard rather than the same machine against itself.