dlaing Posted June 15, 2009 Share Posted June 15, 2009 Dave, remember the part about temp spikes of an air cooled motor. Again, it is only theory but smoothing them out with a small air gap seems to lead to better fueling in hot weather. I remember well. I believe that capping off the curve in the map at a lower temperature will eliminate the negative effect of these "spikes". As we have noted, some bikes, like yours, Ratchet's and mine respond with lean symptoms when conductivity is increased, while Greg Field's, Pete Roper's, their clients, and others respond very well to the increased conductivity. For them the spikes are not a problem, which leads me to speculate they may be running a bit too rich. Some of this variation between bikes may be because the maps and trim settings in the ECUs are not same and some of it is likely just manufacturing variation. When Ryland, others and I came up with a procedure for setting the TPS, we had a heck of time because of the variations. People would try our method, get bad results, and then get better results following more random procedures. I suspect the largest variation is in the trim setting. Most of us have no idea what our trim is set to. Even with my TuneBoy, I can't tell what the trim is set to. I would not be surprised if Moto International and Moto Moda bikes are set to a richer trim than yours, Ratchet's and mine. Unless everyone rushes out and buys VDSTS or Axeone, we will never know the trim settings. The early V11s had a temperature map that will likely aggravate the effects of temperature spikes. The later V11s seemed to "fix" that issue by capping off the compensation curve at a lower temperature. The MGS01 caps off the curve at a lower temperature than any V11. Not being a road legal bike, it's goal is to run well, not pass emissions, so it can do that. I'll be experimenting... Link to comment Share on other sites More sharing options...
Guest ratchethack Posted June 16, 2009 Share Posted June 16, 2009 We want high conductivity and low heat capacity because it allows the sensor to accurately follow the cylinder head temperature. Dave, from now on, please kindly exclude me from your continual misuse/abuse of “The Royal WE”. . .[sigh]. . . I'm hardly EVER likely to be a willing participant in your idea of what "we want". This is just a hunch, but somehow I get the idea I'm not the only one. . . Beyond that, I find your practice of lumping “everyone” in with what you say YOU WANT to be the height of presumption. Speaking for others as a regular practice is also generally pretty arrogant, especially here, considering your complete lack of experience with what you've been merely speculating about when you comment on what is and what is not with regard to the GM plastic air temp sensor, since you've never likely even seen one, let alone experimented extensively with, nor tested one on the Guzzi over thousands of miles, as at least one of us has, and another with possibly less miles, but closing. Despite the extent of your [ahem] formidable Wikipedia education, Dave, you’ve been indiscriminately flinging terms around that you still don’t seem to even remotely comprehend. It seems that Wikipedia hasn't helped you one whit with your grasp of the concept of THERMAL INERTIA. As a matter of fact, the magnitude of your pervasive confusion with many of the terms you've been using is most evident when you provide no clue about what it is you’re referring to when you say, “we want high conductivity and low heat capacity". OF WHAT, Dave? The sensor itself? If not the sensor itself, are you referring to the air gap? Have you yet decided what it is that you’re talking about? The thermo-paste that so many (including myself) have used to provide high conductivity and low heat capacity between sensor base and OE sensor tip? Please allow me to clarify my questions for you with an example. If you’re referring to the sensor itself when you post a statement like, “We want high conductivity and low heat capacity”, The OE sensor is constructed with a solid brass body that encloses the thermistor, so you already have a relatively high conductivity sensor, especially when compared with the GM plastic body sensor, which has practically no property of conductivity wotsoever. The 1.4 oz brass OE sensor also has a relatively high heat capacity in comparison to the GM plastic body sensor, which likewise has practically no property of heat capacity wotsoever. In my statement above about THERMAL INERTIA that you quoted and disagreed with above, I was clear in applying the term to the temp sensor itself. A week ago on this thread, when Velf described his direct exposure of the thermistor in the OE sensor (taking the relatively high thermal inertia of the 1.4 oz of brass out of consideration) by cutting away 15 mm of the thermo-compound-filled brass probe, you said: Kudos! You got rid of most of the thermal inertia! . . . and now you’re saying: Low or high thermal inertia is not what would make sense. ?? ?? Honestly, Dave. Trying to follow your reasoning is more tedious than herding cats. . . Could you please explain how it would make sense to have a sensor with high conductivity and low heat capacity, yet at the same time, high OR low thermal inertia of the sensor is irrelevant? How would you possibly propose to square what you’ve posted above with your Wikipedia definition, which you also posted: The thermal inertia of a material is defined as the square root of the product of the material's bulk thermal conductivity and volumetric heat capacity, where the latter is the product of density and specific heat capacity: . . . since by the Wiki definition, thermal inertia is DIRECTLY RELATED mathematically to both thermal conductivity and heat capacity?? Methinks you’re WAAAAAAAY far off the fairway again, past the rough, through the trees, and on the brink of dropping headlong into your old, familiar Swamp o' Confusion, where you seem so fond of going for extended deep dives. . . I really can’t be bothered chasing your wild shots this far off the fairway, Dave. Frankly, I stopped being interested in your shanked drives off the tee a few holes back. But by all means, play on if you must. . . (Oh, I’m quite sure you will). . . Yet another tough lie Good luck, and see y’all at the 19th hole. . . Link to comment Share on other sites More sharing options...
Admin Jaap Posted June 16, 2009 Share Posted June 16, 2009 I couldn't be bothered to actually count the words of above post that were about telling Dave he was wrong and the number of words that were about temp sensing, but I'm sure the balance is off... Ratch: Telling Dave he is wrong could have been done in 15 words max imo. FWIW: Good writers delete more than half they write... Dan, I'm not going to close this thread (yet) but I'm tempted; sorry... Link to comment Share on other sites More sharing options...
Guest ratchethack Posted June 16, 2009 Share Posted June 16, 2009 I couldn't be bothered to actually count the words of above post that were about telling Dave he was wrong and the number of words that were about temp sensing, but I'm sure the balance is off...Ratch: Telling Dave he is wrong could have been done in 15 words max imo. FWIW: Good writers delete more than half they write... Dan, I'm not going to close this thread (yet) but I'm tempted; sorry... Though once again I have not been charged with a violation of any Forum rule, nor have I been aware that being a "good writer", or that "a balance" of words of some unspecified nature has ever been a requirement for posting here -- let it be understood that as always, I acknowledge that like every Forum poster here, I poach in the King's woods at his pleasure alone, by his permission ONLY, and I suffer no illusions over any non-existent "right" of free speech to claim here wotsoever. I have clearly offended. Please accept my apologies, Jaap. By your leave, I now humbly request permission to withdraw. Link to comment Share on other sites More sharing options...
Admin Jaap Posted June 16, 2009 Share Posted June 16, 2009 By your leave, I now humbly request permission to withdraw. It would suit you if you just would do this w/o pissing people off in the process, including me... Link to comment Share on other sites More sharing options...
Dan M Posted June 16, 2009 Author Share Posted June 16, 2009 Dan, I'm not going to close this thread (yet) but I'm tempted; sorry... It has pretty much run it's course anyway. Not much relevant has been added as of late. It would be interesting to hear from those who have shown interest as to how it worked out for them. If anybody else tries this cheap mod please post to report your results. Link to comment Share on other sites More sharing options...
GuzziMoto Posted June 16, 2009 Share Posted June 16, 2009 Dan, I can respect the approach you seem to have taken with this. And while I don't agree with your theory on temperature spikes, I have no evidence you are wrong. I think you are approaching this in a reasonably sound manor, and while I would prefer to see actual testing complete with temp readings to support your theory, atleast you are thinking it through (unlike some). I have been staying out of your thread on this because I don't agree with the idea of fudging the sensor readings to trick the ECU into doing what you want. But I wish you luck in you experiments and hope you keep at it in a sane, rational manor. Link to comment Share on other sites More sharing options...
Dan M Posted June 16, 2009 Author Share Posted June 16, 2009 Dan, I can respect the approach you seem to have taken with this. And while I don't agree with your theory on temperature spikes, I have no evidence you are wrong. I think you are approaching this in a reasonably sound manor, and while I would prefer to see actual testing complete with temp readings to support your theory, atleast you are thinking it through (unlike some). I have been staying out of your thread on this because I don't agree with the idea of fudging the sensor readings to trick the ECU into doing what you want. But I wish you luck in you experiments and hope you keep at it in a sane, rational manor. Who are you and what have you done with GuzziMoto? Seriously, thanks for your thoughts. I don't look at it as fudging the readings. I'm using the stock holder and my sensor ranges the same as stock. So in essence, I'm sensing the same air space as the stock sensor. No fudging. I believe I'm getting much faster response and avoiding the spikes that are exacerbated by the conducting paste that some (including me for awhile) have added. I am quite sure that a brass encased thermistor sensing air temp is very slow to respond. I still contend that for this purpose, the old style sensor especially with paste is not as well matched to the task as this setup. I have been tremendously busy and to be honest when I have some free time, I've been swinging my leg over the Aprilia more often than the LeMans. That will change though and hotter weather is finally approaching. When I get to do 150-200 miles on a 80F+ day I'll know for sure. I also intend to get it back on my 4 gas analyzer when time permits and compare CO readings to what I had last year. So far though all I can report is good running. Cheers Link to comment Share on other sites More sharing options...
dlaing Posted June 17, 2009 Share Posted June 17, 2009 Dave, from now on, please kindly exclude me from your continual misuse/abuse of “The Royal WE”. . .[sigh]. . . Sorry, but YOU will have to endure. You asked for one simple statement. The trouble with simplicity is that it does not cover all scenarios. If you actually read the full post you would realize you and Dan were excluded from the WE, because it was conditional to having a rich running bike or a willingness to remap to work with the increased conductivity. Beyond that, I find your practice of lumping “everyone” in with what you say YOU WANT to be the height of presumption. Speaking for others as a regular practice is also generally pretty arrogant, especially here, considering your complete lack of experience with what you've been merely speculating about when you comment on what is and what is not with regard to the GM plastic air temp sensor, since you've never likely even seen one, let alone experimented extensively with, nor tested one on the Guzzi over thousands of miles, as at least one of us has, and another with possibly less miles, but closing. It must frustrate the hell out of you that I understand thermodynamics better than you. I have congratulated you and Dan for a fine design and improvement on the OEM, but your theory on it is broken. There is room for improvement beyond your design and Dan's large air gap is questionable. You bury your head in the sand and go lah lah lah lah, avoiding The Truth. Keep those square wheels spinning dude. Despite the extent of your [ahem] formidable Wikipedia education, Dave, you’ve been indiscriminately flinging terms around that you still don’t seem to even remotely comprehend. It seems that Wikipedia hasn't helped you one whit with your grasp of the concept of THERMAL INERTIA. As a matter of fact, the magnitude of your pervasive confusion with many of the terms you've been using is most evident when you provide no clue about what it is you’re referring to when you say, “we want high conductivity and low heat capacity". OF WHAT, Dave? The sensor itself? If not the sensor itself, are you referring to the air gap? Have you yet decided what it is that you’re talking about? The thermo-paste that so many (including myself) have used to provide high conductivity and low heat capacity between sensor base and OE sensor tip? The thermo-paste increases heat capacity, it does not provide low heat capacity. We want high conductivity between the cylinder head and the thermistor, so that thermistor quickly and accurately reflects the temperature of the cylinder head. We want low heat capacity around the thermistor so that the thermistor can quickly follow the temperature of the cylinder head. These are theoretical ideals that are modified by other factors such as an ECU that was tuned for given correlation between thermistor and cylinder head. Without changing the map, increasing conductivity can have a negative for some of us. Your design works better than OEM because you have reduced heat capacity, but you, and especially Dan, have decreased conductivity, which is less than ideal, but according to your detailed scientific analysis with neither a voltage, temperature, or emission reading, is beyond reproach. You claim reduction in spikes is the benefit, but the true benefit is that the air gap lowers the temperature reading so that the ECU does not overly lean the mixture. I am sure your design works fine for you and better than OEM. I have congratulated you for an excellent design. I just have trouble with your theory and explanation, and I see room for improvement. Also, I see why Greg's and Pete's solutions work, which is something you seem to fail to grasp. Please allow me to clarify my questions for you with an example. If you’re referring to the sensor itself when you post a statement like, “We want high conductivity and low heat capacity”, The OE sensor is constructed with a solid brass body that encloses the thermistor, so you already have a relatively high conductivity sensor, especially when compared with the GM plastic body sensor, which has practically no property of conductivity wotsoever. The 1.4 oz brass OE sensor also has a relatively high heat capacity in comparison to the GM plastic body sensor, which likewise has practically no property of heat capacity wotsoever. In my statement above about THERMAL INERTIA that you quoted and disagreed with above, I was clear in applying the term to the temp sensor itself. A week ago on this thread, when Velf described his direct exposure of the thermistor in the OE sensor (taking the relatively high thermal inertia of the 1.4 oz of brass out of consideration) by cutting away 15 mm of the thermo-compound-filled brass probe, you said: . . . and now you’re saying: ?? ?? Honestly, Dave. Trying to follow your reasoning is more tedious than herding cats. . . Could you please explain how it would make sense to have a sensor with high conductivity and low heat capacity, yet at the same time, high OR low thermal inertia of the sensor is irrelevant? How would you possibly propose to square what you’ve posted above with your Wikipedia definition, which you also posted: . . . since by the Wiki definition, thermal inertia is DIRECTLY RELATED mathematically to both thermal conductivity and heat capacity?? Methinks you’re WAAAAAAAY far off the fairway again, past the rough, through the trees, and on the brink of dropping headlong into your old, familiar Swamp o' Confusion, where you seem so fond of going for extended deep dives. . . I really can’t be bothered chasing your wild shots this far off the fairway, Dave. Frankly, I stopped being interested in your shanked drives off the tee a few holes back. But by all means, play on if you must. . . (Oh, I’m quite sure you will). . . Yet another tough lie Good luck, and see y’all at the 19th hole. . . FORE!!!!! The problem with using thermal inertia as an ideal is that it refers to two properties, conductance and volumetric heat capacity that are counter beneficial as they both increase or both decrease. You, apparently, and Dan, certainly have decreased both conductivity and heat capacity and FWIW, also decreased thermal inertia. If you were to maintain the same conductivity between cylinder head and thermistor, and you decreased heat capacity of the sensor body and holder, we can say that thermal inertia was reduced, but it is the decreased heat capacity that was the benefit, because reduced thermal inertia is not necessarily a good thing. If you were decrease conductivity and maintain heat capacity, we would also have a decrease in thermal inertia, but I think WE all would agree that is the wrong way to go. What WE can't seem to agree on is that decreased heat capacity (surrounding the thermistor) and increased conductivity (from cylinder head to thermistor) is the theoretical ideal ( and the real world ideal, IF your bike does not run too lean due to the increased conductivity) What I liked about Velf's solution is that he decreased heat capacity, but he also decreased conductivity, which I question the wisdom of, but like you, he has seen benefits, so more power to him, to you, and to Dan, despite the fact that you have all decreased conductivity. It is pretty obvious that the positive effect of reduced heat capacity outweighs the reduced conductance. I suspect this is largely because the radiation of heat transmits enough to counter the losses due to the insulating qualities of the air. Also FWIW, Heat radiation does not fit into the thermal inertia equation, but is certainly a factor. To sum it up, kudos to you three for doing better than OEM, but the reason is simply reduced heat capacity, and saying that it is because of reduced thermal inertia is misleading. Clunk goes the ball into the 18th hole, in far fewer shots than the master baiter Ratchet, who is wading through the gator filled swamp water trying to find the last of the four balls he brought with him. One lead filled as we might recall, another with a radiator attached, and another wired with resistors. Doesn't the PGA have rules against such play? Link to comment Share on other sites More sharing options...
Admin Jaap Posted June 17, 2009 Share Posted June 17, 2009 It has pretty much run it's course anyway. Not much relevant has been added as of late.It would be interesting to hear from those who have shown interest as to how it worked out for them. If anybody else tries this cheap mod please post to report your results. Topic closed. If anyone wants to post results feel free to start a new topic. 1 Link to comment Share on other sites More sharing options...
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