| Author | Message | ||
     Aaron |
That guy is just amazing to me. Nobody has a right to be as smart as he is. What I really like is how he never answers a question. He has a knack for feeding data instead, and making you figure it out. I guess he figures that if he just tells you, it won't stick. | ||
| M2me |
I was beginning to wonder if the original question, "Which is hotter?" was in reference to the contributors rather than cylinders ;-) That is hillarious!    | ||
| Pammy |
That Ron...reminds me of a southern politician(without the cigar, of course) or maybe a southern baptist preacher, aside from the whole Jesus/God aspect. Jimidan...you gotta be careful about who you hang with. Although anyone who can get 500hp out of a weed eater is someone to be idolized. You can get Ron to 'splain that one to you. ;0} | ||
| Sarodude |
I've found that lotsa really knowledgeable types who've formed complex mental models cannot give simple answers 'cause they know the simple answer can lead the inquiring party astray. Plus, like Aaron said, it would likely aid in learning and UNDERSTANDING to have someone figure it out on their own. -Saro | ||
| Mikej |
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| Blake |
Notsip, I agree, my cheap little IR sensor is not up to par for accurate laboratory measurements. It's guaranteed accuracy is only something like +/-4oF. And you may be correct that an IR sensor will have trouble with highly reflective surfaces. Just like a mirror reflects visible light, a thermally reflective surface can reflect the heat of surroundings as well as emit its own heat. Other than highly reflective surfaces though, I'm pretty sure that an IR sensor is fairly accurate. I also agree that my IR sensor is not the optimum device for distinguishing between root and tip temperatures of the fins. I simply adjusted the position to find the highest and lowest local temperatures and assumed (uhoh ![:]](http://www.badweatherbikers.com/buell/clipart/proud.gif) ) that they corresponded to the root and tip temperatures respectively. Careful, the results of your oil filter IR temperature measurements while on the surface appear to indicate that the IR sensor is not able to accurately measure the surface temperature of the chromed filter, you have made an assumption that the chrome filter was just as hot as the black painted filter. I agree, that is *probably* the case, but in my "real world" experience so many times, such assumptions have come back to bite me. Not trying to question your conclusions, just trying to impress upon those reading this the rigors that true conclusive scientific experiment and testing entail... basically... NO assumptions. The anal scientist would need to measure oil temperatures immediately up- and down-stream of each filter as well as actual contact surface temperatures (via thermocouple or thermistor) in multiple places on each filter and also via IR sensor. We would also need to ensure that ambient conditions surrounding each filter were identical... same airflow, same proximity/orientation to any radiative heat sources. See how something that seems initially to appear so straight forward, simple and easily conclusive, may in fact be extremely complex? One thing that strikes me about the MT cylinders is that they are very robust looking with even the fins being much thicker than those on the stock cylinders. That would tend to diminish the effectiveness of the cooling fins. It might also explain why you saw anomalous results in measuring the temperatures at the fin tips on iron and aluminum cylinders. When you say "temperature probes" are you talking about thermocouple or thermistor devices that are adhered to the cylinder or are you using something else? Jimidan, The paint you are talking about aids in radiative heat transfer, an it is a valid application. I don't know of any paint that would aid in the conductive or convective transfer of heat in aluminum or from aluminum to air. The paint would be most effective in helping to cool the engine in the absence of cooling air flow, like when stopped in traffic or on parade duty. Side note: The design of cooling fins is a very interesting science. Trying to determine the optimum thickness, spacing, orientation and length involves a LOT of considerations. | ||
| Mikej |
"Side note: The design of cooling fins is a very interesting science. Trying to determine the optimum thickness, spacing, orientation and length involves a LOT of considerations." It also involves a lot of remodeling of CAD files. I think I wore out a mouse once doing that at a local outfit for some underwater self propelled device with an internal engine of sorts. Imagine trying to cool an engine inside an enclosed chamber without cooking the occupants of said device. Kind of like baking chocolate chip cookies without melting the chocolate chips.  I have no idea what this has to do with the discussion. | ||
| Court |
>>>>Imagine trying to cool an engine inside an enclosed chamber without cooking the occupants of said device. Sorry dude...you are light years behind technology. The breakthrough in this field was a highly developed, albeit intuitive, device called the Volkswagen Type I Beetle. I had a spanking NEW 1967 in Zenith Blue (commemorative color for the last year of the Type 1) in the garage until 1998. But....it cooled the engine, in the enclosed shrouding, so well that it required a down coat in the winter. The "air cooled heating" (is that an Ox or Moron?) worked. But, as I recall, without the benefit of a frickin' IR Themometer accurate within +/- whatever Kelvin, it required that the car be driven at a speed of 60PMH in 2nd gear for 862 miles to produce a 7oF increase in cabin temperature. Anyone wanna calculate the Kilocalories and stuff....don't MAKE me get my text books out! Germans....I love them. When you guys are done, someone explain how I've ridden all these miles completely oblivious to the temperatures, absolute and relative, of all the various points on my cylinders. I feel so...so...so USED !  Court | ||
| Mikej |
"Sorry dude..." Errr, not an option on the stuff I was dealing with, kind of hard to aircool while underwater.  And they didn't like the heated water being vented to the outside water too much either. Kind of like leaving a jetstream in the sky, only different. | ||
| Notsip |
Blake, All I was trying to relate is the temperature differences between two different types (colors) of filters. You are exactly correct in your assumption the the reflection plays a major role in the difference of temperatures. The temperature probes used in our testing are type "K" Thermocoupler. Liquids are measured with a thermistor. As far as the difference in cylinder fins are concerned you can investigate that on your own. You are the genious in that department and I will let you figure it out. As I stated before we only tested what the consumer is available to purchase over the counter, nothing special. | ||
| Jimidan |
Aaron wrote: "What I really like is how he never answers a question. He has a knack for feeding data instead, and making you figure it out. I guess he figures that if he just tells you, it won't stick." Maybe that is why the term "best" is not in Ron's vocabulary! Pammy wrote: "That Ron...reminds me of a southern politician(without the cigar, of course) or maybe a southern baptist preacher, aside from the whole Jesus/God aspect." Nice analogy, there Pammy! In fact, I have really enoyed your contributions in this thread...they are soooo testosterone free. You are pretty funny yourself. and continued: "...anyone who can get 500hp out of a weed eater is someone to be idolized." I can't wait to hear that one! and Court added: "When you guys are done, someone explain how I've ridden all these miles completely oblivious to the temperatures, absolute and relative, of all the various points on my cylinders." Actually, that was in the same vein as the last thing Ron said today in closing our conversation...just get out and ride the damn things and have fun! That sounds like an excellent idea right now...bye! | ||
| Captpete |
Thanks to all the respondents to my plea for help w/ the barograph. I think I got it covered now. I, too, have had an hour-long conversation with Ron. My advice to anyone calling him: Before you dial that number, have a recorder standing by. | ||
| Blake |
Notsip, Thermocouple, check. Thanks for the reply. FYI, a thermistor is not a device that is especially suited to measuring temperatures in liquids any more so than a thermocouple. The two sensors are just different types of thermo-electrically sensitive devices. A thermocouple produces a voltage corresponding to temperature. A thermistor's electrical resistance varies with temperature. One is thermo-voltaic, one is thermo-resistive, either can be used in many different applications. For temperature sensors, thermocouples are by far the preferred device. I still cannot imagine why, other than the paint coating on the aluminum cylinders being significantly more insulative, how the iron cylinder fin tips could be hotter than those on the aluminum cylinder. Makes no sense at all. Maybe some time you'll get the chance to test an unpainted aluminum cylinder versus an iron one. It would seem like valuable information to understand the effects of the paint. | ||
| Pammy |
"I've ridden all these miles completely oblivious " Court...honestly, dearheart, sweetypie, did you truly think this was ground breaking news? ;0} We use a Power-Coating on some cylinders to disapate(sp?) heat. As a matter of fact, we use it on iron and aluminum cylinders. The problem with these bikes is not a question of which cylinder gets hotter. It's how can we stop it or slow it down. And unfortunately, the only answer is, you can't stop it. It's the nature of the design(flaw). So we try to abate it as best we can. And one of the many tools do do so is the oil squirter that Dan(Notsip) offers. I am using it. So far so good. Still testing it. We are using them on the most abused and abusive motors. I also use a plethora of coatings to help repel heat, move heat along, and stand up to the heat. We also use cam design to help with the cooling process. This is all we can do for now. Another thermo-tester is the inside of your lower, right calf. If that burns to the point of leaving a scar...your motor is toast. ;0} | ||
| Pammy |
Blake, maybe you can do some mathematical equations of the effects of scar tissue on diminishment of accurate testing.%o} | ||
| Notsip |
Food for Thought, My thoughts on heat disipation on cylinders and cylinder heads ( and this may be antiquated and I may need corrected)is that if left in an uncoated condition that they would expell heat better as air moves over it. My thoughts are that a rough and porous casting (the rougher the casting the better) would allow the cooling air that passes over the fins to draw more temperature out of the material whether cast iron or aluminum. And if the fins were painted or powder coated that it would be sealing up all of the porosity in the castings and would not allow the heat to escape. Which would not allow it to cool as quickly. Example: When we port our cylinder heads we have found by removing all of the roughness in the combustion chambers and exhaust ports and polishing it to a semi mirror finish, it reduces the amount of heat that is radiated out through the head from the combustion chamber and ex port. We know this to be fact from our testing. So wouldn't painting, powder coating and polishing (in a sense sealing) the outside of the casting keep the heat contained inside the casting? But when you speak with a powder coater they say that this is not true. Is this statement from them fact, fiction or a marketing ploy to obtain a larger market base just like the crank vent product? Blake (The Thermo-Man) this should be one that you are familiar with, so help us out. | ||
| Captpete |
Pammy You almost stepped outta the closet there. Or is it let the cat outta the closet? You know the ultimate test is still ahead. (No pun intended. It just happened.) I forgot to call that guy again yesterday. I will take care of it today. | ||
| Aesquire |
It's been a while since my buds RD400 jugs & heads heating in his kitchen oven got him beat about the head by a broom when his wife came home from work, but they did look nice. Gun-Kote is the brand name I remember. http://www.kgcoatings.com/gun-kote/ http://tenring.com/trcoating.html  | ||
| Jimidan |
Pammy said: "And one of the many tools do do so is the oil squirter that Dan(Notsip) offers. I am using it. So far so good. Still testing it. We are using them on the most abused and abusive motors." Do you use squirters on cast iron, aluminum nic-sil, and iron sleeved cylinders indesciminately? If not, what criteria do you use to apply this technology? Aren't all big twins and new XB9 Buell engines equiped with like squirters? What criteria do you use to determine which kind of cylinder you recommend to a customer? What is "Power Coating"? I assume it is a type of high tech powder coating that goes on the outside of the cylinder and is baked on, but how does it work? thanks | ||
| Pammy |
Petey...you mean I almost threw your bony ass outta the closet.... Jim...we have used them on cast iron and on aluminum. Like I said, we are still testing. One coating goes on the outside, one on the inside, another on the combustion chamber, piston top and valve face, one goes on the valves stems and valve guides, one goes on the piston sides, and then there is the super special coating that goes into the exhaust port. I may have overlapped a couple of coatings...I'm tired and cranky(what's new). The criteria we use to determine a cylinder material is the same criteria used to determine cam design, head design, etc... We are not as closed minded as to say one is better than another. I will say one suits a certain application better than another. And with that you can add most any product.... | ||
| Pammy |
Jim, when I said aluminum, I meant nikasil coated aluminum.... | ||
| Blake |
Effect of pitting and porosity on heat exchange... Seems like it would take a lot of porosity to have any significant effects. If internal to the fins it would impede conductance of heat from fin root to fin tip. Even exposed pitting/porosity would impede the ability of heat to flow from root to tip of fins. The pitting/porosity effectively reduces the volume of the available pathway through which the heat can travel. So for conductivity, the travel of heat within a conductor, excessive pitting and porosity would be a bad thing. With respect to convection, exchange/transfer of heat from one medium to another via fluidic interaction (at least one medium must be fluid)... Exposed pitting would reduce the amount of surface through which the air flow can interact. Small pits would most likely contain pockets of stagnant air. The picture below shows how the pitting (grey areas) in metal(blue) would tend to insulate the flow of heat (red) against being transfered from the metal to the air stream (light blue).  The pitting could tend to aid radiative heat transfer, but not appreciably. I'm very interested in the effects of the various coatings, specially those used on the combustion chamber surfaces. | ||
| Jimidan |
Pammy said: "One coating goes on the outside, one on the inside,..." When you say on the inside, are you talking about a coating that goes on the inside of the bore of the cylinder? | ||
| Captpete |
I'm very interested in the effects of the various coatings, specially those used on the combustion chamber surfaces. Well, stand by, old buddy. You ain't near as interested as I am. The true test is yet to come. And Pammy's sandbaggin' you a little. She didn't mention the quadruple-coated..... (We'll see whose ass comes flying outta the closet!) | ||
| Captpete |
Pammy's probably gone to bed, Jimidan. But I can answer that one for you. One coating is designed to inhibit heat absorption (inside) and the other to maximize radiation (outside). Capt. Pete | ||
| Pammy |
Jim, yep Petey...we can only pray it's not my big ol' ass.....maybe everyone better stand WAY back just in case!!! | ||
| Captpete |
I wasn't going there. | ||
| Captpete |
Don't ya think ya oughta tease Blake a little with that heat sink thing? | ||
| Captpete |
Nah, never mind. | ||
| Steveshakeshaft |
I too have wondered about these coatings, more particularly those internal to the engine. Many questions spring to mind, for example presumably there is a mis-match between thermal expansion rates. How does the coating a) Stick to the piston/combustion chamber in cold/hot/cold cycling? b) Not crack? Steve www.ukbeg.com steve_s@ukbeg.com |
