Discontinue GYTR Comp ECU Bootup FI Map Self-Adjustment? When?


31 replies to this topic
  • grayracer513

Posted January 13, 2014 - 09:51 AM

#21

(KoolAid) and GrayRacer have basically agreed with each other ..

 

I don't think that's the case.



  • mebgardner

Posted January 13, 2014 - 10:09 AM

#22

I don't think that's the case.

 

I'm inviting you to elaborate. On which point do you feel there's still disagreement?



  • grayracer513

Posted January 13, 2014 - 10:49 AM

#23

Read posts two and ten, and then tell me what you think I agree with TKAMMS on.  I think it would be simpler.



  • mebgardner

Posted January 13, 2014 - 03:48 PM

#24

OK, I get it.  I had to read and re-read a few times, but I think I understand the reason.

 

I started the divergence by stating that I believe the FI system we have on our WR450's is "open loop", and took exception to our system being compared to a modern auto design with a "closed loop" system.

 

I wrote that a difference in viewpoints between you and TKAMMS could be accounted for by this fact.

 

You kindly gave me a schooling on closed loop systems operation. I thank you.

 

There are obviously several people who don't at all get the meaning of "closed loop" as used in reference to electronic engine controls, or the function of an oxygen sensor. 

 

"Closed loop" operation exists where a system uses an oxygen sensor to provide feedback information from the exhaust stream to the ECU that shows the more or less precise mixture state the engine is currently running in.  If it reports "too rich", the unit adapts.  Likewise a report of "too lean".  This is determined by reading the difference in temperature on the upstream and downstream sides of the sensor probe. The sensor does not actually measure oxygen content, it "determines" it from this information.  But there are two very important things to know about this.  The first one is that the oxygen sensor is fairly slow to respond to changes, and can't deal with a very wide range of temperature differences, so they are incapable of proper operation at or near full throttle, and are completely inactive beyond about 2/3 throttle.  Above that, the engine is using its most recently modified map.  "Closed loop" exists only when rolling along at a steady speed under "cruising" loads.

 

The second thing is that oxygen sensors don't work until they arrive at around 600 ℉.  This means that they are inoperative on cold starts.  However, the system "knows" immediately what the air density is as soon as it's powered up by using information from the BARO (barometric pressure) sensor and IAT (intake air temperature) sensor.  Fuel distribution IS adjusted based on this information regardless of how and when it happens to change.  None of this occurs in a "closed loop" state, and and oxygen sensor has no part in the matter.  There is no technological reason that a system without an OS can't completely adapt itself to changing ambient conditions on the fly.

 

The "loss of performance" experienced at high altitude will occur regardless of whether the unit adapts itself or is manually remapped to adjust fuel delivery for the simple reason that there is less air per cubic foot going through the engine.  Higher altitudes cause a too rich condition in an unadjusted system, lower the dynamic compression, and lowers the flash point of liquids.

 

So, I inferred that, since you did not dispute that the WR450 is "open loop", that you agreed (inferred) that it *is* open loop operation.

 

 

So, this statement is where the difference still remains:

 

"There is no technological reason that a system without an Oxygen Sensor can't completely adapt itself to changing ambient conditions on the fly.".

 

... and, given your description of closed loop operations, I will not disagree.

 

 

The difference is, TKAMMS was relaying information that he was given while investigating a problem with KTM FI.  Those Throttle Body devices and ECUs used on the KTM are reportedly the same hardware that we use on our WR450 FI, until modified by KTM or Yamaha (or other OEMs).

 

 

You're asserting "it should just work" open loop for the entire range of available (software / firmware / hardware) adjustment, and requesting proof that it's not so. He's asserting the manufacturer reps he spoke to, say it's not so, and he cant prove it. It's compensated over a small range of adjustment (+/-5 %) and that's it.  More adjustment requires a manual "reboot" using a manual procedure.

 

 

So, OK, I get you're skeptical and you have good reasons.

 

 

Would you please give me a bit more schooling (I'm a glutton for punishment) on the benefits of closed loop systems. That is, if it should just work open loop, then why the NRE (engineering) expense of implementing closed loop? Is it due to EPA restrictions?



  • f150jokerstyle

Posted January 13, 2014 - 04:57 PM

#25

 

Messed up disregard. P.s. I don't like smart phones lol


Edited by f150jokerstyle, January 13, 2014 - 05:04 PM.


  • f150jokerstyle

Posted January 13, 2014 - 04:57 PM

#26

 

messed up disregard.


Edited by f150jokerstyle, January 13, 2014 - 05:03 PM.


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  • f150jokerstyle

Posted January 13, 2014 - 04:57 PM

#27

OK, I get it.  I had to read and re-read a few times, but I think I understand the reason.

 

I started the divergence by stating that I believe the FI system we have on our WR450's is "open loop", and took exception to our system being compared to a modern auto design with a "closed loop" system.

 

I wrote that a difference in viewpoints between you and TKAMMS could be accounted for by this fact.

 

You kindly gave me a schooling on closed loop systems operation. I thank you.

 

 

So, I inferred that, since you did not dispute that the WR450 is "open loop", that you agreed (inferred) that it *is* open loop operation.

 

 

So, this statement is where the difference still remains:

 

"There is no technological reason that a system without an Oxygen Sensor can't completely adapt itself to changing ambient conditions on the fly.".

 

... and, given your description of closed loop operations, I will not disagree.

 

 

The difference is, TKAMMS was relaying information that he was given while investigating a problem with KTM FI.  Those Throttle Body devices and ECUs used on the KTM are reportedly the same hardware that we use on our WR450 FI, until modified by KTM or Yamaha (or other OEMs).

 

 

You're asserting "it should just work" open loop for the entire range of available (software / firmware / hardware) adjustment, and requesting proof that it's not so. He's asserting the manufacturer reps he spoke to, say it's not so, and he cant prove it. It's compensated over a small range of adjustment (+/-5 %) and that's it.  More adjustment requires a manual "reboot" using a manual procedure.

 

 

So, OK, I get you're skeptical and you have good reasons.

 

 

Would you please give me a bit more schooling (I'm a glutton for punishment) on the benefits of closed loop systems. That is, if it should just work open loop, then why the NRE (engineering) expense of implementing closed loop? Is it due to EPA restrictions?

 

 

 

Again watch the link I have posted.

 

 Everything that greyracer has stated from what I can tell is ture. What he has done is given you the technical break down of what YAMAHA them selfs have claimed the Wr450 in the video can do.

 

Also as Grey has mentioned along with myself that higher elevation = lower engine performance. The higher you go there is no amount of tuning in the world that will make any engine at 12k ft have as much raw power at 0ft.

 

If it were me asking these questions I would not be inclined to believe some guys on an internet forum over Yamaha them selfs. 


Edited by f150jokerstyle, January 13, 2014 - 05:07 PM.


  • mebgardner

Posted January 14, 2014 - 06:37 AM

#28

OK, F150, I'll watch it soon...



  • f150jokerstyle

Posted January 14, 2014 - 06:56 AM

#29

As the old saying goes you can lead a horse to water but you can't force em to drink...

  • mebgardner

Posted January 14, 2014 - 06:59 AM

#30

I'll state that one reason I'm willing to listen to what TKMMS has written about the bounded limits of control available from the algorithms embedded within the (stock) ECU is, I work in this field.

 

When he writes that the amount is limited to +/-5%, what I read is that a SW algorithm developer for the FI control loop decided that, since there are fewer system sensor inputs to supply data, that he has to consider the loss (a failure) of one of those fewer sensors.

 

In my work world of developing complex embedded systems (HW, SW and FW), we do this *all* the time.  We bound the limits of the control loop, in the SW algorithms, based on fault tolerance, and then we consider what kind of "default mode" can be tolerated if a sensor *is* failed.

 

In this case, I'm suggesting the system SW developer decided that the best he could do was to limit the amount of automatic compensation based on when sensor data is available / good, and then default to that limit when / if a sensor was to fail. Then we, the users, "live with" the 5% limit until we fix it.

 

Allowing the system to automatically compensate to the limits of the *hardware* upon a sensor failure may have allowed the ECU to command the ignition retarding right into detonation, or leaning fuel into starvation.

 

I'll give a real world example. My SUV experienced a failure of the "knock" sensor.  When it occured, the ECU algorithm advanced the ignition timing to the max positive limit. It's programming dictated that, since it's sensor input data could not detect a condition of "approaching detonation" (which provides fuel efficiency when approached), then the "safe" control law was to push ignition timing to "max advanced". My fuel MPG sucked, and I had little power from the go pedal. But, it survived until I repaired it.  That's the point: the system survived the loss of the sensor data.

 

I dont know this for sure, but, based on my work experience, and reading what TKMMS wrote about what he was told (3rd party), I still find it *plausible*.

 

So, I'm really done writing about this now. It is what it is, and mebbe some day we'll know for sure (when someone publishes the algorithms, yeah, right).



  • mebgardner

Posted January 14, 2014 - 07:01 AM

#31

As the old saying goes you can lead a horse to water but you can't force em to drink...

 

What?  I have promised to watch it. I'm at work, so I'm not gonna watch it right now. Be patient.



  • f150jokerstyle

Posted January 14, 2014 - 06:14 PM

#32

What?  I have promised to watch it. I'm at work, so I'm not gonna watch it right now. Be patient.

 

Sorry I thought you were being a smarty pants.

 

I can to a point, understand your train of thought from your last post but I find it not very plausible that this is the case here.

 

Regarding post #51 in the link you provided I think that I may have found the misdirection / misinformation given.

 

I downloaded the European 2013 wr450 manual and read threw it. This the break in procedure in it's entirety that is listed. If you compare post #51 from your original link and this, they are very similar. Maybe this is where the confusion/assumption that this has to do with fueling/ignition occured. I do not see any where in this following information that this procedure is for that but even if it is, it fairly clearly states this is only for INITIAL START UP and not every time you ride the bike. Again this is from the European manual so maybe it does not apply but I found it interesting none the less.

 

 

1. Before starting the engine, fill the fuel tank with the fuel.

2. Start and warm up the engine. Check the operation of the controls and the engine stop switch. (See page 3-7.) Then, restart the engine and check its operation within no more than 5 minutes after it is re- started.

3. Operate the motorcycle in the low- er gears at moderate throttle open- ings for five to eight minutes. Stop the engine.

4. Check how the engine runs when the motorcycle is ridden with the throttle 1/4 to 1/2 open (low to me- dium speed) for about one hour.

 

5. Start the engine and check the op- eration of the motorcycle through- out its entire operating range. Restart the motorcycle and ride it for about 10 to 15 more minutes. The motorcycle will now be ready to ride normally.

After the engine break-in period, thor- oughly check the motorcycle for loose parts, oil leakage and any other prob- lems. Be sure to inspect and make ad- justments thoroughly, especially cable and drive chain slack and loose spokes. In addition, check all fittings and fasteners for looseness, and tight- en if necessary.

ECA15560

NOTICE When any of the following parts

have been replaced, they must be broken in. Cylinder or crankshaft: About one hour of break-in op- eration is necessary.

Piston, rings or transmission gears: These parts require about 30 minutes of break-in operation at half-throttle or less. Observe the condition of the engine carefully

during operation. If any engine trouble should oc-

cur during the engine break-in period, immediately have a Yamaha dealer check the vehi- cle.






 
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