In regards to the fins cooling an aircooled motor, I believe that oil still does the major % of cooling in any motor, period.

Any more feedback on that severe shock oil in the tranny?
I put in the HD stuff for my first gear oil change and I have not been happy with the shifting. The stuff that came out looked and smelt like regular gear oil anf to me seemed to shift better.

 

You have to be kidding about oil does the major percent of cooling toa motor.

By your logic I can cut off the fins on my HD, or plug the fan on my lawn mower that supplies air to the cooling fins. By your logic the water in my car radiator is only there to assist the oil in cooling the motor. Oil does not cool a motor at all. Oil lubricates and spreads heat from part to part in the motor. This is not a cooling action. Some motors and not Evos have problems with oil getting to hot, such as tow vehicles and may need a oil cooler. A oil cooler on a Evo is a big mistake as it will makeyour Evo oil runto cold.

This is the first I have ever heard that oil cools the motor a major percent. You might want to rethink that statement.

 

Sorry you are right, I meant to say almost half.

Motor oil also creates seals around engine parts that make your vehicle more fuel efficient and powerful. Since motor oil seals out the air, your engine is protected against corrosion and the elements, which could lead to rust and system break-down. Motor oil not only protects your engine and keeps its parts running smoothly, but it also carries heat away from many parts of your engine that coolant can’t get to. Almost half of engine cooling is done by motor oil.
This even more important on an air cooled motor because there is no water jacket at a controlled temp. to dissapate heat.
On some bigger motors oil is splashed on pistons to cool them and natural crankcase heat cools it.
Oil also does a hell of a job cooling some of the metal machinary I use every day.
Mind you I have never owned an Evo so maybe I don't know
Try reading Lubrication Fundamentals by J George Wills

You may want to also rethink your statement that oil does not cool a motor at all, think friction

 

Sorry you are right, I meant to say almost half. Not quite but you are getting close.

Motor oil also creates seals around engine parts that make your vehicle more fuel efficient and powerful. No seals do that oil only lubricates the seals. Since motor oil seals out the air, your engine is protected against corrosion and the elements, which could lead to rust and system break-down. Motor oil not only protects your engine and keeps its parts running smoothly, but it also carries heat away from many parts of your engine that coolant can’t get to. Close, oil distribute heat and lubrication.Almost half of engine cooling is done by motor oil. Again no. The bulk of your motor heat is in the heads where the heat explosion occurs. Air or water cool this. This is where your fins are located on a air cooled motor and where the water jacket is on a water cooled motor.
This even more important on an air cooled motor because there is no water jacket at a controlled temp. to dissapate heat. The oil ports are very small on all motors and cannot cool a motor by any stretch.
On some bigger motors oil is splashed on pistons to cool them and natural crankcase heat cools it. Oil is splashed on all pistons to lubricate, even 2cycle motors as the gas/oil mix heads up to the cylinder.
Oil also does a hell of a job cooling some of the metal machinary I use every day. Now you are talking about a differantdog. In yourmachinary case oil is your coolant and pushed past your parts in quanity. Motors get only a fraction of that amount circulating through the block. I have also seen machinary cooled with a white mix of oil and water. Depending on what you are cutting like stone a machine cutter will use water as a coolant, For metal cutting oil is that best coolant due to rust.
Mind you I have never owned an Evo so maybe I don't know. All motors are the same. Evo is no differant than your car, except Air cooled or water cooled. I have never heard of a motor that is oil cooled.
Try reading Lubrication Fundamentals by J George Wills. I understand lubrication, but I thought we were talking about cooling?

You may want to also rethink your statement that oil does not cool a motor at all, think friction. Again friction is lubrication, not cooling. Oil does distrubite heat so that your motor is uniformally hot and not heated only at certain spots. Think about this. Does oil cool you tranny? No, it lubricates it. Does oil cool your primary. No, it lubricates it. Your tranny does not get hot enough to need cooling. Your motor does get hot enough to need cooling due to those explosions, about 2500 a minute does produce allot of heat. Oil does not cool a motor by defination, it lubricates.

Again the bulk of your heat is in the heads where the explosions occur. It is the heads that are cooled by the fins or water. Start your bike and touch you motor. See what gets hot first. The oil distributes that heat down to your block. This can in no way be considered cooling.

Oil does not seal out air. Seals do that. Oil lubricates those seals so that they do not wear out.

I hope this helps clarify thing for you.

 

So, heat transfer cannot be considered cooling... I'm learning more every day....

Just a little additionalinfo. Many engines on the market have "cooling" jets located in the crankcase to distribute oil to the bottom of the pistons. Only a very small amount of that oil is directed to the wrist pin. It is primaraly for "cooling" the piston.. Some even have cooling passages in the piston head, over the top combustion ring, fed by the cooling jet from the bottom,to aid in "cooling" not lubrication.(as someone trained by the manufacturer and its engineers, I think I have a good idea of the facts behind that statement)...

No one is arguing the fact that oil is primaraly a lubricant. An air cooled engine does need "air" to cool it. However, the oil WILL absorb more heat due to normal heat transfer.. (ever fried chicken on the stove??? The oil gets hot, doesnt it??) The oil must be cooled to keep from breaking down and oxidizing. This is much more critical on an air cooled engine than a water cooled engine because there is no water to transfer heat and the air transferis not as efficient... So, is it a coolant, thats depending on your view. kind of like the chicken and the egg question.


Why dont they have sealed bearings in them then? If the oil doesnt cool by reduction of friction, why couldnt they eliminate the parasitic drain of the oil splash by just running a dry box with sealed, no maintenance bearings.. It would be great, save money and maintenance too..

 

Just a little additionalinfo. Many engines on the market have "cooling" jets located in the crankcase to distribute oil to the bottom of the pistons. Only a very small amount of that oil is directed to the wrist pin. It is primaraly for "cooling" the piston..This may be so but it is not a major percent of the cooling of a motor.Some even have cooling passages in the piston head, Lubricating which stops heat in the cam.over the top combustion ring, Again that islubricating the piston.fed by the cooling jet from the bottom,to aid in "cooling" not lubrication. The oil ther does cool the bottom of the piston, this is not a major percent. (as someone trained by the manufacturer and its engineers, I think I have a good idea of the facts behind that statement)...

No one is arguing the fact that oil is primaraly a lubricant. An air cooled engine does need "air" to cool it. However, the oil WILL absorb more heat due to normal heat transfer.. (ever fried chicken on the stove??? The oil gets hot, doesnt it??) What the heck does this mean??? The oil must be cooled to keep from breaking down and oxidizing. Show me the oil cooler on the Evo. This is much more critical on an air cooled engine than a water cooled engine because there is no water to transfer heat and the air transferis not as efficient...It has been ok for yearsSo, is it a coolant, thats depending on your view. kind of like the chicken and the egg question. Now a chicken and a egg???

I am sorry but I am going to stop at this point. As you back pedal your original statemant the oil cools a major percent of the motor. I can see that a trained machinest, trained by the manufcture and it's engineer concerning oil cooling a internal combustion engine.Or are we talking about oil cooling the part that you are cutting on the machine? Not a dig to your profession as I was a machinest at one time.

Although I do agree with oil stops heat through lubrication. That is not a cooling action. Here is a fun fact for you, start a gas engine withoil in it. then take out the oil and start the same motor. It will run for hours. No oil in it. Now place that no oil motor under load and it will break in seconds or minutes. Due to lack of lubrication. Does that tell you anything? Metal is its own best heat conductor.

I am done with this topic, so from here on think what you want.

 

Yea I'm done with it too.. The fact that you think I'm backpeddling on the issue of cooling shows you have no idea what I'm talking about nor are you listening to what I have to say.. I'm not the machinist you are refering to, though he seems to be more reasonable. Ihave been refering to the internal combustion engine until I had to make a reference to oil absorbing heat, which obviously wasnt quite as simple as I thought it was.. Maybe its the way I'm presenting the info I'm trying to put out there...

One last clarification for the others who may still be reading this. Some pistons have oil passages in them strictly for cooling purposes around the rings, believe it or not.. In a stock engine, I'm sure you can get away with just about any oil you chose with proper intervals..

Article on piston cooling where the above quote came from. Just a quick reference to the fact that oil does provide cooling to the engine..

Take it for what you will guys, I'm out of here.....

 

The bottom paragraph about sealed bearings in the tranny kind of threw me offI guess. I could not understand why talk about sealed bearings in atranny that needs lube for all of the gearing. No offence but it sort of made everything else make no sence to me. My mistake for not looking at who wrote it, and for me not looking at the bigger picture on what you were stating.

My mistake and apology on mixing you up with another. I do and did agree that the bottom of the piston is cooled by oil. Again I apologize, I mixed you up with someone else and thought you were back pedaling. HGM, I have noticed in the past that you do know what you are talking about.

I am not a new rider. 35 years agoI bought my first HD. My current Evo I bought new in 89. 19 years ago. Sometimes I have a shorter patience concerning those that do not know but continue to argue their belief. I am sure that you understand.

 

89 FXRS, I can see you have a pretty good idea of what you are talking about too. The more I read of your posts, I understand your point of lube first. I just disagree about the idea cooling is as minimal as you do though. I'll try to clarrify what I was talking about for you though, you certainly dont have to agree. My point on the fried chicken was simply the transfer of heat that takes place to oil in simplistic relation to an engine transfer of heat to oil. It absorbs heat, therfore it is providing a cooling effect of its own.

The bearing reference was refering to the statement that oil doesnt cool in a tranny. It cools in the manner that it prevents friction. By preventing friction, it keeps heat from building. Therefore a sealed bearing, needing no lubrication, still wouldnt work. The gears would gaul and eventually overheat and melt. Which thought all brought on the chicken and egg. Does oil cool heat or prevent heat? Either way, in my mind its acts as a coolant. In yours, I believe, it keeps the engine from needing a coolant. Kind of the same thought..

I accept your appology, though it may not be appropriate, and offer my own for over reacting. This topic got out of hand some time ago and explaining ones views with simple typed words is sometimes very difficult and can cause frustation... I'll also offer up a truese. Turkey season is open here and I'm going to try to talk to a few..

 

i went with moble 1