I will look tomorrow ... not sure just now but I need to pull it out since I have been asked about the flywheel by another member and have yet to check for them.

Hey all! I still think Lancer is on the right track. Looking at the oil path from pump to filter housing, it's pretty direct. Unplugging and connecting the the two threaded plugs adds an additional path, with the same beginning and end. You would get some flow through it, but without plugging or modifying the area within the blue circle, the oil would tend towards its original path. I think the oval or disk is an illustration of the oil path going through from one casting to the next. (separate crankcase and filter housings?)
Lets just say for example my guessing is right..... (usually NOT) ...if someone were to add an oil cooler and it wasn't elevated too high or restrictive, a bit less that half of the oil would be cooled, while the remainder scoots through the original path. This is probably not a bad thing.... The original oiling isn't altered, so the system will be up to pressure almost as quickly as without the cooler. AND even if only 30% finds it's way through the cooler, that still adds much more cooling capacity to a bike that was doing "okay" without it. I still think its a win-win improvement,and it can't hurt. I seriously hope to try it soon. Those of us in the hotter climes definitly need all the help we can get.

Yarr, word has it the speedo isn't that accurate once you're into the extralegal speed range.

I normally run 67-70 on the local four-lane highway (65 mph limit) and it's pretty much the flow of traffic which I'm left assuming is at the speed limit. Then when I see a THP patrol car sitting in the median, I still can't help but slow down to an indicated 65 mph...and all the other vehicles gain ground on me. Oh well. Better safe than sorry!

I look forward to seeing how this oil cooler thing goes if you're gonna do it, Jerry. The issue with the piping seems to be a serious crux though.

Regards,
Banger
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I spent some time studying the cases yesterday and am confident of my statement.  They may have designed those plugs for a drain and test port, but if you connect them together with just a short line ... or a longer one with a cooler in between, there will be SOME FLOW  THROUGH THE LINE..  It may not be a lot of flow, but there will be some.  The oil is now flowing through the one passageway identified in the pic and if a second passageway is created then the oil will also flow through that as well.  It may only be 1/3 of what the first line flows, but it will flow.  There is no other way for it to go.  It will not be static, the oil will move on up into the filter through both doorways.  The oil pump has pressurized the oil just prior to the passageways and it will force the oil through both lines.  It will not back up and stop the flow to the second line because the oil will go up to the filter instead of down into the second line.
Sorry friend, no offense, but that is what will happen.

i have an oil cooler (ada racing ithink)that was on my ct 70 clone when i had a modified engine..the motor is a horz. thumper .the kit came with banjo fittings, lines, and a new cam cover plate with a different oil path milled in to force oil to the cooler then back to the end of the cam..the top of the cooler was  higher than the highest point of the head ,it worked fine..
with lines and cooler the system took apx  3 ozs more oil
so the  dip stick read over full when the oil drained back down...maybe b4 next oil change will go to the hydralic shop and have some fittings and lines fabbed( if my money tree decides to fruit this year)it cant hurt  in these 100f days.....

    Man, are we all Armchair Oil Coolers or what? Hahahaha! Just kidding. I LOVE engine theory.
    Here comes my worthless 2 cents.... I'm thinking that unless the engine is raced, run flat out or under severe stress, a person would probably want the oil to get up to temperature, just not overly hot. I think even if only 1/3 of the flow goes through the cooler, it'll still be a really good thing.
    On a somewhat related experience, I had a car with auto-trans... when it needed a bigger radiator, I Assburgered it by putting a radiator with no tranny cooler and then put an aftermarket cooler on in its place. That tranny NEVER got any hotter than hot bathwater! I was all proud of myself until a friend who repairs trannies says that while overheating the oil is bad; too cool of oil won't lubricate as well and still not be a good thing. The circuit is supposed to get to at least engine coolant temp (175F) to work right.
    Sooooooo.... That little bypass port will help the engine get up to temperature quicker at low-load speeds, and as you're blazing down the freeway, the oil cooler will be doing its thing.
    I will try it, but I'm still Baby-Stepping these mods. My "improvements" usually end up being anything but. My Savage is my "Family Car" so I gotta be careful!

JerryAssburger wrote on 12/31/69 at 16:00:07:


Awesome. I can sorta relate, although I have a Nissan pickup that seldom gets driven through nearly three of the four seasons...it's the "backup vehicle" I guess. At any rate, it's hard to make myself too anxious to try something this immense and touchy, since it might mess with reliability.

Perhaps we should take our case to Suzuki R&D and see if they would consider making future S40s with an oil cooler? They're putting oil cooler on all their larger C-series bikes now, from what I've seen. They must understand the cult following this little bike has! If they realize that, then maybe a unified voice calling for improvements on the engine (especially in the form of an oil-cooler since it doesn't cause more pollution and is a win-win more power-more reliability modification) would make sense to someone at the ol' home office.

Regards,
Banger
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Hey Guys what do you think of that, it's an oil thermostat, put it between the engine and the cooler and it returns oil to the engine bypassing the cooler untill the engine is up to temp.

Pretty cool !

Clive W