Oil Cooler

Yes optimal oil temp drove me bonkers to track down in air cooled engines. Best I
came up with is close but not quite water boil temperature. There is
a new product invention that gives up 30% more fuel mileage, by preheating
the oil entering engine to thin it for less pumping loss and internal shear friction.
Again realize oil cooler in our cast iron cook stoves is just to protect the oil not the engine directly. But it still gets to denaturing temperature/time in the head, so nothing for it but change oil often enough and use best oil that don't break down too fast.

Ms Peel OIF using whole LH frame tube to return oil to spine and then it fills the whole RH frame tube to draw directly from. I have oil temp at butt end of spine and am prepared to insulate the spine if it don't get to over 160 F, short of some special endurance or speed attempt. Will put on oil gauge too but know it not to be paid much attention too. ugh.

I plan on extra pump to jet pistons and hope the oil pump can suck out the excess, but jets will only come on with hi boost and rpm, not sitting still or legal use.

steveyacht said:

Getting back to the thermostat issue...... what would be the optimum operating temperature for the engine oil? I am assuming by the responses that somewhere in the 180 to 195 mark should provide a nice stable temp that will burn off contaminants while allowing ZDDP additives to do their job properly, partiicularly in the head.

Opinions Please?

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The oil people say 213F minimum and preferred 215F . Jim

By far the Coolest oil cooler was designed by Goldwaithe[sp] who put probes in engine to monitor. It was a side cover with machine fins block with sleek art deco face exposed in middle of cover. But if boiling hot is best then what's that imply on wisdom to install a cooler even with thermostatic, ugh.

ZZDP is not one molecule but a range of forms and each has optimal activation temperature but only the manufacturers know as not listed on label specs.
I've looked into heat pipes installed in head but dropped that idea and will just have to change oil like everyone else should and not idle as long and low as I'd like too. If gets too hot on long hi speed events I'll just add another water tank to spray outside too and me in summer blistering air temps.

The one I have decided on is made by JAGG. Their products are designed around HD motorcycles. It begins to open at 185 and is fully open at 195, becoming fully closed again at 185. Very compact and light unit only 1.5"x1.5"x.75" with .75" hose barbs. Sounds like a nice compact unit that will get the job done that I am looking for.

Actually another very appealing part from HD that Ms Peel looked at. If you are taking 190' F oil straight out engine to cool, then by time it gets to tank and then to engine its cooler than optimal. Logically it should cool oil after tank just prior to engine but what a plumbing hassle and risk of gravity feed starvation. I've gone round and round on this and still trying to convince myself I'm not mis guided against my own gut feelings on cool oil is gooder. But then again just how much harm are you doing if oil is cool going into engine? OIl should heat up on interfaces to from the ZZDP protection, I think, so really don't know how to advise myself or others.

One of my many unfinished projects was building an oil cooler into a fastback tailpiece, all the air was going to be supplied by a couple of tube axial fans blowing out past the number plate. Some day.....

Sounds like might be poor thermal decision to dumb ole me. We already know Nortons are most coolest at their stillest and oil cooler not a help - but say the fans take like 100 watts to flow enough to matter [~1/8 hp], that means bigger battery to lug around for decent time to set still or idle fuel burn set higher = more heat, to keep up with fans or drop volts till stalls. Yet I love the idea and wish it made more sense to me to do it too dang it. In others words fans may add more heat load on engine than removes by cooler oil tickle at slow rpms. Oil don't stay long in engine but does in tank so less under seat heat may be nice. But so little heat generated at idle may be a wash for the extra coolness mod factor.

Old school method was just put vents in the side cover.

hobot said:

Sounds like might be poor thermal decision to dumb ole me. We already know Nortons are most coolest at their stillest and oil cooler not a help - but say the fans take like 100 watts to flow enough to matter [~1/8 hp], that means bigger battery to lug around for decent time to set still or idle fuel burn set higher = more heat, to keep up with fans or drop volts till stalls. Yet I love the idea and wish it made more sense to me to do it too dang it. In others words fans may add more heat load on engine than removes by cooler oil tickle at slow rpms. Oil don't stay long in engine but does in tank so less under seat heat may be nice. But so little heat generated at idle may be a wash for the extra coolness mod factor.

Old school method was just put vents in the side cover.

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It may or may not work but brushless DC fans and blowers (like in a PC) dont use much power at all and are pretty good at moving lots of air. I like the idea of the cooler in a fast back even if it was just added bling

It's much easier to get thermostatic control, just turn the fans off on a simple thermostat, no fancy plumbing needed.
So if its coolest at idle the fans won't be running anyway.

I use Morris 40 straight when I can get it (not so easy in Canada). I think its a very reasonable compromise and a good oil.

Silkolene 40 is second best. I'm not sure I'd feel good with a 30 weight but I see what Hobot is getting at in hotter climates.

L

I"ve had at least two events that lowered oil by at least half in high summer heat with lots of twisties to attack all by myself and have topped off with 30 grade for lawn mower or cars someone had on hand and took off w/o a worry knowing I was just carrying away more heat and temp gauge proved it. Never hooked up oil PSI gauge but we know the official recommendation on those decorative things, ei: if ya pay too much attention to it you will not ride and should remove it. ugh.