GuzziMoto Posted March 30, 2009 Posted March 30, 2009 Sorry, but RH will have to try harder if he is going to convince me (or any one else with two brain cells to rub together) that the sensor has more thermal inertia then the cylinder head and that the large chunk of aluminum we call the cylinder head can heat up and cool down faster then the little piece of copper and brass that is the ETS. And if you add thermal goo or a brass holder, that will only increase the heat flow between the two making them even closer to the same temp. And no the cylinder head temp does not change as rapidly as RH believes. The engine is a large chunk of aluminum and is not prone to sudden changes of temp. In fact a liquid cooled motor will heat up and cool down faster, although once heated up it will tend to be more stable then the air cooled motor. And how is it that the airflow that RH says suddenly cools down the cylinder does not cool off the ETS. I guess it does not transfer any heat to the air unless you give it a heat sink? The engine is the source of heat and the ETS measures it. The ETS will not heat up higher then the engine and being much smaller it can change temp faster then the engine can. Edit; 38, I can almost taste it.
raz Posted March 30, 2009 Posted March 30, 2009 When, for example, the smoke escapes from an electrical component (like, say, a Lucas voltage regulator), it will be observed that the component stops working. The function of the wire harness is to carry the smoke from one device to another; when the wire harness "springs a leak" and lets all the smoke out of the system, nothing works afterwards. Starter motors were frowned upon in British motorcycles for some time, largely because they consume large quantities of smoke, requiring very large wires. Yeah, how did we miss this?
Dan M Posted March 30, 2009 Posted March 30, 2009 Yeah, how did we miss this? Ha! Fabulous. I've been witness to more than one Lucas part porous enough to let the smoke out. Little did I know they sold replacement smoke. I wonder how much the equipment is to inject it back into the component.
Greg Field Posted March 30, 2009 Posted March 30, 2009 If Ratchet and I actually agree on something, you guys really need to question your understanding of thermal dynamics. Everyone is fine with Greg's duct tape???? Is everyone living on the North Pole riding in the snow with square wheels???? What's your problem with my duct tape? It's a rather poor, token attempt at insulating the sensor, yes, far less insulative than the plastic of the stock sensor housing. I really should insulate it beeter. My guess is you're trying to say I should nopt insulate it at all, and that's just bassackwards. Really, I'm coming to believe you and Ratch are losing your minds over this. But at least we're now one page closer to the magic 40. Buy stocks short, soon . . .
savagehenry Posted March 30, 2009 Posted March 30, 2009 Negative ground systems as used by the V11 depends upon proper circuit functioning, which is the transmission of charged ions by retention of the visible spectral manifestation known as "smoke". Smoke is the thing that makes electrical circuits work; we know this to be true because every time one lets the smoke out of the electrical system, it stops working. This can be verified repeatedly through empirical testing. From the basic concept of electrical transmission of energy in the form of smoke, a better understanding of the mysteries of electrical components - - even those on the V11 - - is gained by the casual user. Sooo...you're saying that we humans, like our V11's, are run by electricity.... And some people say that my negativity keeps me grounded.... Emperical evidence now leads me to believe all those years I was paying for a particular herbal substance and thought I was getting "tuned in", I was really just leaking electricity ?!?!? NOW I know why they are refered (reefer'd?) to as "Wasted Years"...and I totally dig yer whole "mysteries" thing, that's very heavy Man, but I was WAY MORE than a casual user...Sorry Ladies and Gentlemen, don't let me stop you in your pursuit for that elusive page 40! P.S. Hey big J, I think you are leaking electricity, Dude
zenben Posted March 31, 2009 Posted March 31, 2009 BQ ? Thermal dynamics ? Square tires ? Bottled smoke ? Awesome Has anyone blamed this sensor issue on AGW yet ?
dlaing Posted March 31, 2009 Posted March 31, 2009 My earlier comments in Grey, new comments in black, and GuzziMoto's comments in blue I think we now have two definitions of accuracy. There is the accuracy of the sensor following the engine temperature, and there is the accuracy of the sensor output matching the table in the ECU. Adding goo helps the sensor follow the engine, but we really aren't sure about how it matches the table in the ECU. It appears that adding goo makes it better match the table at cold temps and at hot temps it is a worse match. There is only matching the sensor temp (and therefore it reading) to the temp of the engine. The table in the ECU is what the ECU does with the information the sensors send it. There is no "sensor output matching the table in the ECU". Again, causing the sensor to read low will trick the ECU into giving the motor more fuel at all rpms, and that may seem to correct an issue with the bike being lean at low revs and throttle openings. But it will also add more fuel at higher revs and throttle openings that the motor does not need, not to mention it does not address what was causing the lean condition to begin with. It is a band-aid fix that treats the symptom, not the problem. The table in the ECU represents temperature and voltage. The temperature and voltage numbers were matched at the factory with a stock setup. Anything that changes the temperature reading from stock deviates it from the temperature in the ECU's table. Saying that goo increases the accuracy is only true because it increases the engine temperature to ambient air temperature ratio. But the accuracy that the engineers intended is compromised, for better and/or worse. Guzzi engineers may have figured on making it nice and rich at temperatures that won't be tested for emissions. As for it being too rich at higher RPMs and throttle openings, I don't think that is true, except for a couple of cells on the map. As evidence, look at the PCIII map for a stock Guzzi, where almost all changes are to make it run richer indicating it was too lean to begin with. Emissions testing is not done at full throttle and high rpms so Guzzi and most others (especially with air cooled motors) set the bike up either with correct fueling or rich fueling in those areas. It is only in the lower revs and throttle openings that the motor is lean, and there it should not be so lean that it runs as you describe having issues with unless something is not right with the bike. This is not something unique to Guzzi but most if not all the manufacters do this. But that raises another point about what the temperature was when the bike was dyno'd. How do the tuning link dyno? I seem to recall they hold it one throttle position and let it go through the revs, and then move to the next throttle position getting more and more open as they go, so probably the engine is probably coolest under low throttles and hottest at high throttles, throwing off the values. Any decent dyno operator will keep an eye on engine temp to prevent that from happening. Depending on your definition of keeping an eye on engine temp, that could be scathing remark to dyno operators. To be a decent dyno operator do you have to be a cyborg with an infrared eye? Another problem is that many dealers may be doing the "favor" of setting the trim (or TPS) richer than EPA mandated spec. Adding goo may be seen to have a positive effect because of that. Adding goo has a positive effect because it gets the bike off of the rich warmup mode quicker then it does without the goo, thus reducing fuel consumption and in most cases improving warmup time (a rich motor will warmup a little slower then on with correct fueling, plus over rich fueling can wash oil off the cylinder walls). The purpose of the ETS is to tell the ECU when the motor is cold so it will add more fuel. That is what it does. Anything you do to improve it accuracy will give the ECU better more acurate info on the temp of the engine. Screwing with that in a way that feeds the ECU inaccurate info is not or will it ever be defined as improving the accuracy of the sensor. It will alter the fueling but it is not improving the accuracy. You cannot put a heatsink on the sensor and then say it is improving the heat flow to the sensor by drawing heat into the sensor. It is doing one thing and one thing only, it is cooling off the sensor causing it to read lower then it should. Call it what you like but it is doing what it does. Heatsinks shed heat cooling off the device they are attached to. But adding goo screws "with that in a way that feeds the ECU inaccurate info"!!! Yes it will increase fuel efficiency, especially during warm-up, but it also causes the temperature to deviate from the engineers intended and it causes the ECU to lean the bike out too much at high temperatures, especially during cool-down (something Ratchet is addressing!)
dlaing Posted March 31, 2009 Posted March 31, 2009 Sorry, but RH will have to try harder if he is going to convince me (or any one else with two brain cells to rub together) that the sensor has more thermal inertia then the cylinder head and that the large chunk of aluminum we call the cylinder head can heat up and cool down faster then the little piece of copper and brass that is the ETS. And if you add thermal goo or a brass holder, that will only increase the heat flow between the two making them even closer to the same temp. And no the cylinder head temp does not change as rapidly as RH believes. The engine is a large chunk of aluminum and is not prone to sudden changes of temp. In fact a liquid cooled motor will heat up and cool down faster, although once heated up it will tend to be more stable then the air cooled motor. And how is it that the airflow that RH says suddenly cools down the cylinder does not cool off the ETS. I guess it does not transfer any heat to the air unless you give it a heat sink? The engine is the source of heat and the ETS measures it. The ETS will not heat up higher then the engine and being much smaller it can change temp faster then the engine can. Edit; 38, I can almost taste it. The sensor and plastic housing does not have more thermal inertia than the cylinder head, but it lacks enough thermal diffusivity that it SIGNIFICANTLY delays following the temperature of the cylinder head, which does in fact vary enough to cause significant changes in running characteristics of the bike. The most drastic changes occur during startup and shutdown, and that is where we see the greatest lag time for the sensor trying to keep up with the cylinder temperature. The ETS does not "heat up more the engine" but the engine could conceivably cool down to a lower temperature than the sensor, when you shut the engine off, and maybe even during some operating conditions, such as coasting down a mountain. Whether or not it does, is not really relevant, but what is important, is how much the sensor temperature is lagging behind the changes in cylinder temperature.
dlaing Posted March 31, 2009 Posted March 31, 2009 BQ ? Thermal dynamics ? Square tires ? Bottled smoke ?Awesome Has anyone blamed this sensor issue on AGW yet ? What is AGW? German Auto Workers union??? I think Ratchet blamed his inability to test under ideal test conditions on a lack of AGW!
dlaing Posted March 31, 2009 Posted March 31, 2009 What's your problem with my duct tape? It's a rather poor, token attempt at insulating the sensor, yes, far less insulative than the plastic of the stock sensor housing. I really should insulate it beeter. My guess is you're trying to say I should nopt insulate it at all, and that's just bassackwards. Really, I'm coming to believe you and Ratch are losing your minds over this. But at least we're now one page closer to the magic 40. Buy stocks short, soon . . . At first I saw some value to insulating the brass adapter, because it increases the ratio of engine temperature to ambient air temperature, and I liked the idea of shielding it from cold rain and high wind speeds. I was assuming that because the sensor and housing are smaller, the weather would more quickly effect the sensor temperature than the engine temperature, but the cooling fins on the engine are comparatively much more massive then on the brass sensor adapter, and the nature of aluminum vs. brass helps make the brass cool off and heat up more slowly. Putting the brass adapter on a lathe to shave off the cooling fins would do wonders for the thermal diffusivity, and making the adapter out of billet alloy aluminum would be even better! I have had issues that show the sensor is getting too hot, (of course it could be solar flares) so insulating is the last thing I would do, unless I lived in Seattle, and even then, I would probably only insulate the base of the adapter, near where the sensor tip is located, and not the sensor body that needs to stay cool. Of course some voltage readings on my bike showing it never getting over 100C with Goo added would certainly convince me of the value of insulating. And FWIW, Huberts readings show otherwise. Pete Roper's readings weren't detailed enough.
Skeeve Posted March 31, 2009 Posted March 31, 2009 But adding goo screws "with that in a way that feeds the ECU inaccurate info"!!!Yes it will increase fuel efficiency, especially during warm-up, but it also causes the temperature to deviate from the engineers intended and it causes the ECU to lean the bike out too much at high temperatures, especially during cool-down (something Ratchet is addressing!) No. Adding the "goo" doesn't cause the temperature to deviate from what the Guzzi engineers intended: it merely enables the sensor to follow the changes in cylinder head temp. more closely; the incorrect fueling at high or low temps is exactly as intended. Adding a heatsink similarly does not cause deviation from the factory settings, but again allows the sensor to track the reduction in CHT more accurately rather than its own accumulated stock of heat [1] since it is so shielded from airflow and has such limited surface area thru which to shed heat (via radiation or conduction.) Here's the deal: The stock CHT holder has a brass base [for conducting heat from the cylinder head to the sensor], and a thermoset resin upper half [to insulate the sensor from excessive heat transfer from the body of the sensor, vs. the conduction via the sensor tip.] Complaints about this sensor center around its delay in allowing the sensor to come up to temp when riding in cooler environments and the propensity for structural failure upon removal attempts. But here's the deal: the stock sensor holder never needs to be removed in the general scheme of things! The sensor can be unscrewed, some thermal conduction goo added, and screwed back in. Hey presto, my fingers never leave my hand - magic! The brass sensor holder [that was stock on the 1100 Sporti?] was replaced because it allows too much heat transfer, even with attempts to reduce this effect by "finning" the brass body. What's funny is that the gap between the sensor tip and the inside surface at the bottom of the hole the sensor screws into is about 2x that of the plastic sensor holder! So the more rapid changes to fueling in cool environments experienced by users of this part [whether stock or retrofit] is entirely due to heat conduction via the sensor body, rather than via the sensor tip! Sorry, I'd post pics if I had 3 hands & the time to futz about with this, but I just measured a plastic holder vs. the brass SxS today & spent some time thinking about what the differences between the two parts meant. Moral of the story: add the thermal goo to your plastic sensor holder while the part is relatively new & unlikely to fail upon removal of the sensor, and don't worry about it after that: you've expended minimum effort to resolve one of the biggest of the cold weather riding concerns. Add a little heatsink to your sensor if you ride someplace warm, to counteract negative f/x of the "goop" in that performance regime. Any fueling problems after that are factory-induced [lets not reminisce about how badly Mandello has bungled the FI maps in the past (Centauro, anyone?)] and can be cured by one of the competing aftermarket means of injection-map rectification... Cutting and splicing into the wiring harness to add the resistor per Ratchethack's exerimental experience is an option for those who want to have the ability to dial in a little extra fuel & subvert the Guzzi engineers' idea of what the proper fueling should be, but at that point I think I'd rather just go with one of the other ways to doctor the entire map, not just confusing the ECU by twiddling the heat sensor... Meanwhile, it's your ride, do what you want with it! I'm still interested in reading about your experiments, even if others think you're nuts... [1] I'm really dreading all this talk of "inertia" etc. in reference to the heat sensor, for fear that soon the whole topic will degenerate into descriptions of "caloric" & phlogiston, but there you have it...
dlaing Posted March 31, 2009 Posted March 31, 2009 No. Adding the "goo" doesn't cause the temperature to deviate from what the Guzzi engineers intended: Nonsense! It absolutely causes the temperature to be hotter. Add a little heatsink to your sensor if you ride someplace warm, to counteract negative f/x of the "goop" in that performance regime. Now you are talking! You are admitting that the goo causes the temperature to deviate from the engineers intended, right? Or are you saying the engineers intended to add goo?
GuzziMoto Posted March 31, 2009 Posted March 31, 2009 Okay, this is pretty simple stuff. ANYTHING you do to increase heat transfer between the cylinder head and the ETS will also increase heat transfer the other way, from the ETS to the cylinder head in the off chance that the ETS finds it self in the position of being hotter then the cylinder head. Its a two way street. AHYTHING you do to increase heat transfer between the two parts will increase the accuracy of the ETS. ANYTHING you do that decreases the heat transfer or adds cooling to the ETS will decrease the accuracy of the ETS. The table is not a chart of values that Guzzi engineers came up with after running the engine to heat it up to certain temps and then measured the output of the sensor at that temp and wrote it down. It is based off a spec sheet for the sensor giving sensor outputs at given sensor tip temps. There will be NO consideration in that chart for deviations caused by lack of heat transfer or anything else. The biggest flaw in most of RH's theory (and yours) is that most of the V11's do not have these temp related issues. If the stock setup was flawed and/or made worse by adding goo then all the bikes that have done so would be running worse, not just a few. If your still not sure, please reread the first two parts.
Greg Field Posted March 31, 2009 Posted March 31, 2009 I'd advise you to stop talking sense, Guzzimoto, but I really want to see 40 pages. Think it's possible to make them lose their minds even more thoroughly? Let's try . . . The mass of the copper insert in the stock holder is so miniscule compared to the mass of the head that the time delay for it coming to the same temp as that of the mass (versus the tips of the fins) of the cylinder head that I doubt the lag is greater than 2 seconds, if even that. It conducts heat just as efficiently back to the head as from the head to the sensor tip. That's why they used copper, which is a very expensive material. Therefore, assuming good contact or thermo goo, the small mass of the sensor tip added on will delay it maybe another 2 seconds. It's a short-term transient difference that cannot cause a steady state fault like poor running when hot at idle. If this were what were causing it, after a few seconds, your idle would return to normal. You're baying at the base of the wrong tree.
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