Well it's an F frame but I have already scrapped the idea (anybody want to buy an oil cooler!!  )

Quote from: sledge on February 11, 2013, 03:33:08 AM

Quote from: mcg2000 on February 10, 2013, 10:45:10 PM
Just a useful note, even though the engine shouldn't run too hot on you as-is, an oil cooler will increase the efficiency of your engine. I'm not saying it will save you $1000 over the life of your bike, but it will make you more eco-friendly.

How and why?

Well, to explain that would be a very in depth engineering lecture, but just know that a cooler engine runs more efficiently. Also, cooler intake air increases efficiency too. Basically, you want to avoid hot things (make them cool as possible for efficiency) if what's providing your power is the combustion of fuel and air.

This is why you see inter-coolers (heat exchangers like your radiator) on some air-intake systems. And, obviously, why oil-coolers exists.

If you really want to know why this is so, I will at least point you in the right direction. Pick up a used "thermodynamics" textbook for cheap and just check out a few chapters. The calculations will most likely bore you, so I recommend sticking to the descriptive paragraphs instead of the formulations. 

Quote from: mcg2000 on February 12, 2013, 09:24:48 AM


Well, to explain that would be a very in depth engineering lecture, but just know that a cooler engine runs more efficiently. Also, cooler intake air increases efficiency too. Basically, you want to avoid hot things (make them cool as possible for efficiency) if what's providing your power is the combustion of fuel and air.

This is why you see inter-coolers (heat exchangers like your radiator) on some air-intake systems. And, obviously, why oil-coolers exists.

If you really want to know why this is so, I will at least point you in the right direction. Pick up a used "thermodynamics" textbook for cheap and just check out a few chapters. The calculations will most likely bore you, so I recommend sticking to the descriptive paragraphs instead of the formulations. 

Interesting and probably far above my head. I also had pondered the benefits of adding some kind of oil cooler to my naked 02 GS given that I live in Australia and on some days it gets very very warm here. Sitting in traffic makes me sad for my little air cooled twin.

Based on some of other posts in this thread it sounds like the bike will probably outlast me on a hot day anyway.

Cheers for everyone's info!

Quote from: mcg2000 on February 12, 2013, 09:24:48 AM

Well, to explain that would be a very in depth engineering lecture....... SO TRY ME

but just know that a cooler engine runs more efficiently...... DEPENDS HOW COOL 

Also, cooler intake air increases efficiency too...... AGREED BUT WHATS THIS GOT TO DO WITH OIL COOLERS?

Basically, you want to avoid hot things (make them cool as possible for efficiency) if what's providing your power is the combustion of fuel and air......... NOT TRUE, ENGINES NEED A MINIUM TEMP TO OPERATE EFFICIENTLY AND OPERATE WITHIN PARAMETERS

This is why you see inter-coolers (heat exchangers like your radiator) on some air-intake systems.... INTERCOOLERS COOL THE INCOMING AIR MAKING IT MORE DENSE, THIS ALLOWS MORE AIR/FUEL PER CHARGE AND IN TURN MORE POWER PER CYCLE.....

And, obviously, why oil-coolers exists......   OBVIOUSLY    ??.....OIL COOLERS COOL OIL, NOT THE INCOMING AIR

If you really want to know why this is so, I will at least point you in the right direction. Pick up a used "thermodynamics" textbook for cheap and just check out a few chapters. The calculations will most likely bore you, so I recommend sticking to the descriptive paragraphs instead of the formulations. IAM FAR TOO BUSY, WILL YOU DO IT PLEASE

Personaly I think you are confusing intercoolers and oil coolers and believe they do the same thing and serve the same purpose    

....meander wander dawdling ... Ooh lookit !! Fireworks!! .. Seat and popcorn time!! .. 

... (Throws some Karmal candy popcorn at Sledge) .. Sic em Ken!

I thought the only reason that the newer GS's got an oil cooler is because other aircooled motorcycles have oil coolers in them...

Maybe also to run different types of oils (Dinosaur vs Synthetic, etc) which may be more affected by higher temps you would usually find in an aircooled engine...higher oil temps tend to be detrimental to lubrication (more viscous, less lubrication). Maybe the oil cooler was put on as a "just in case" rather than a "requirement".

I didn't need an aircooler on my first bike, even when the air temps would get into 50c/122F plus, pretty sure something as bulletproof as the GS can handle it...

If you are stationary, the oil cooler is only a place where another pint of oil can sit.

The oil cooler only functions when you are moving: i.e. air blowing across it.

Thing where a radiator is to dissipate heat have a fan to blow the air when you are stationary. Like the radiator on a Nina 250: there is a fan. Without the fan, the bike would overheat.

Same for our oil cooler's radiator. There is no fan on it. If you're stopped, it does a good amount of squat.

So maybe the radiator is there just for looks? If you are moving, enough air flows over the engine without needing the oil cooler.

Alright Sledge... initially I didn't want to explain it, but then I thought it'd be a good review for me.

  First off, when I say cool temperatures, I mean the range of "cool" in engines, not ice. I know engines have a minimum safe operating temperature. As for your intercoolers interjection, you are right. However in addition to cool air having a higher density than hot air, it is also easier to compress. In a controlled volume compression process, such as a piston in a cylinder, hot air requires more energy to compress, thus putting more of a work load on the piston. Now, I assume you want a defending description for that.  Here it goes. If we consider stage 1 being the piston at bottom dead center (BDC) with a cylinder full of uncompressed air, and stage 2 being the piston at top dead center (TDC) with the air now compressed fully (but not yet ignited), then we can describe the pressures and temperatures as T1, T2, P1, and P2.  From what's referred to as the "Otto Cycle" (I recommend looking up pictures of the graphs of "Pressure versus Volume" and "Temperature versus Entropy"), which describes the 4-stroke engine combustion process, we can see that P1 is less than P2. When you increase the pressure of a controlled volume substance, such as that in a compression stroke of a piston from stage 1 to 2, the temperature of the substance also goes up. You can see this by comparing two corresponding P-V and T-s graphs. To calculate the efficiency of this process, the variable "eta," you simply apply the equation eta=1-(T1/T2). From the ratio of T1/T2, you can see that the larger T1 is, or the temperature of your incoming air, the less efficiency you have. Thus to increase efficiency from stage 1 to 2, you either must heighten T2 or lower T1, and since your compression will always result in the same P2 (ideally, but in reality it will vary so slightly that it's considered negligible), increasing T2 is not really viable. What is viable though is decreasing the inlet air temperature T1, and that's where the intercooler comes in.
  Now, you said something about intercoolers versus coolers. Technically, they're all heat exchangers, meant to transfer heat energy to the air by means of convection. In fact, the oil cooler and an air intercooler are both transferring heat from fluids to another fluid, because gas (air) is a fluid (gas just further defines the state of fluidity, when applicable). I don't plan on searching through any text to find any equations relating engine oil temperature to efficiency, but here's an explanation. I saw someone on here mention that oil viscosity is affected, and that directly affects how well the engine is lubricated. This is true. If you take that one step further, you will see that a less lubricated engine will not only have more friction, but more wear as well. Friction is an opposing force which counters what you're trying to accomplish in an engine. Thus, the more friction there is, the less efficiency you have because the harder you have to work to get the same result. Note that you obviously must have friction in most, if not all engines for proper operation. But letting it get too high is bad (and I'm not talking about extremes such piston seizure). So applying this to our case, the heat exchanger (oil cooler) helps release some of the oil's heat to the ambient air, and as Adidas stated, stagnant air barely helps. So while he is right that sitting still doesn't help a heat exchanger much, it still makes a heck of a difference when you're moving. Trying not to break off too much on this tangent, the faster you're going on the bike, the more load is on the engine because of drag, or air resistance. The more load, or work, on the engine, the more heat it will produce. So at highway speeds, you can be dang sure that the oil cooler is doing a fantastic job.
  Now, to say that the engine fins do fine without the cooler may be true, but I would assume that the oil cooler, as I said before, increases efficiency of the engine. To compare the efficiencies of an oil-cooled engine versus a non-oil-cooled engine would be a heck of a lot of calculations, and no one's paying me... so screw that.
  So I will state this again, Sledge. Oil coolers and air intercoolers exists for the same reason, to increase efficiency. In the cases of extreme engine temperatures, a coolant system would be used, not an oil cooler (that would be a poor design choice).
  Also, please don't ask me for proof of the equations such as the derivations. If you want information that in depth (and frankly boring), you gotta open up a textbook or look online. They all source from the 1st and 2nd law of thermodynamics.

Hopefully this helped the OP as well. I'm not all familiar with the oil pathways of an oil-cooled setup in a GS500, but I doubt you can install one without changing the engine block.... well, not same way as a stock one. You can always drill and pipe your own system, but I'm not recommending that either.

http://gstwins.com/gsboard/index.php?topic=62499.0

- Bboy

mcg2000,

I don't really have time to pick apart your comments, but I think you are somewhat off-base. It's fair to say that colder intake temperatures are better, but I don't think it's reasonable to say that engine's are more efficient when cool - there are efficiency trade-offs all over the place with engines; e.g. fuel tends to condense in a cold engine, resulting in a poor burn.

The oil cooler is beneficial in controlling the GS500's oil temperatures. There is a lot of reasonable belief that it was added to address cooling concerns when the fairings were introduced.

mcg2000, have you ever turned a wrench at a professional level on a internal combustion engine?

Quote from: mcg2000 on February 14, 2013, 01:06:06 PM
Alright Sledge... initially I didn't want to explain it, but then I thought it'd be a good review for me.

  - snip a lot of stuff about cold air -

  Now, to say that the engine fins do fine without the cooler may be true, but I would assume that the oil cooler, as I said before, increases efficiency of the engine. To compare the efficiencies of an oil-cooled engine versus a non-oil-cooled engine would be a heck of a lot of calculations, and no one's paying me... so screw that.

So after all that bloviating, still no proof the oil cooler is Needed, rather an admission you don't have a clue. Seems you didn't hand it to Sledge as you might have thought.

Bloviating .. I like it.... (Checks to see if its real) ... It is!! 

Cheers Mister ... New word to use next week!! 

This thread took a turn for the.... well...... it took a turn

Errr yeah... Sorry ... Kinda .... Sometimes it's fun to watch the 'techspec-ies' go at it though... Seeing who can shout their brand of right the most ...

"Give a home mechanic a completed project and suddenly it's like they worked 20 years wrenching in a factory team" ...

I do the very basic bits on my ride... Tried some more serious stuff and realised I don't have the patience for it ... So now I just appreciate everyone's ideas mostly ..... And most of the ideas/concepts would work.. Or do work ... But the path travelled varies... End of day if it works its ok

For OP,   Just fyi,  all earlier engines, I mean from the gs400's from 1980 to I think 2006 GS500 blocks were the same with regard to the oil passages.

After that the bottom half of the block was changed.

The bottom oil pan was fitted with oil in and out fittings and the bottom case has a few extra passages to allow oil to flow in and out using those fittings through the pan.

As to whether or not to install an oil cooler;  I would.  Its not necessary, this engine has survived just fine without it but a cooler engine is better no matter what.  But for me that means changing blocks just to add a cooler.  I'm still working on another way to do it using an external pump on a thermal switch and a cooler to circulate just what is sitting in the bottom of the engine.

hope this helps.

The current naked model GS500's sold in Australia are still sold without an oil cooler. Only the F model has them. 

Quote from: Suzuki Stevo on February 15, 2013, 08:23:59 PM
mcg2000, have you ever turned a wrench at a professional level on a internal combustion engine?

  I'm not looking to prove anything on this site, as most anyone well knows an online debate will never end. I stated what I knew on the Otto cycle. Assume what you will about my mechanical experience. The whole point of that description was to help back up what I already tried to say earlier, and I'll state the final conclusion again. It's probably not worth putting an oil cooler on. Too much work, not enough benefits.

  To keep this from becoming a "tard farm" post, I wont reply to anymore of these comments on what I've said. You either believe it or you don't. It's what I've learned in engineering and the engineering world is always evolving, so please, if you feels its wrong, look into it, prove it wrong or advance it, and help it evolve! The faster it evolves, the quicker I get to be a space man! 

Quote from: mcg2000 on February 12, 2013, 09:24:48 AM
Well, to explain that would be a very in depth engineering lecture, but just know that a cooler engine runs more efficiently. Also, cooler intake air increases efficiency too. Basically, you want to avoid hot things (make them cool as possible for efficiency) if what's providing your power is the combustion of fuel and air.

I was just curious about your mechanical background because your blanket statement above is more wrong than right, I came from at least 3 decades of carburated engines that required heat added to the intake to make them run correct/efficiently (out of the box) remove the hot air and they ran like crap.

Have you ever seen an engine with round vacuum diaphragms at the end of the snorkels? Their function is to do just the opposite of your statement above..that's all I was getting at.



And on that note, Fuel Cooling Cans, Cold Air/Ram Air on a carburated engine is all about getting a colder more dense mixture of fuel/air into the cylinder for a bigger bang when lit....but it's not the most fuel efficient way to go, mileage wise.



I might as well add this also...you can clearly see what warm air does for fuel efficiently. (at least for an '04 Prius?)

  Engine operating temperatures are the limiting factors. Those engines with the "snorkel" required hotter air to operate correctly. The Prius thing has way too many factors. It's not just ambient air, you also have the chemistry behind the battery life at different temperatures and all sorts of stuff (friction factors of the road, density of air for drag, etc.). The list goes on and on. Also, please don't take my "increase efficiencies" as some huge MPG increase. A increase in efficiency of the Otto cycle from 35% to 38% will barely reflect in the MPG's, especially in the range your graph shows.
  I initially had this reply as something else because the difference between a carb intake and a fuel injected air intake sparked my interests, but I later realized that the Otto cycle efficiencies come strictly from compression in the cylinder, so it doesn't matter how it got there. I corrected myself but realized I could modify the posts, so I changed my next post to "disregard." I didn't want to leave this one blank and have 2 "disregard" posts with no explanation.
  I really don't think any of us will come to an agreement though. So let's just agree to disagree.