BDM Oil Cooler

Energy One

BWG56

Guru
I dont see a dividing wall, I think you would lose efficiency without something.

With this being a low pressure system, I assume you would want to have something to ensure the flow back down is restricted just enough to maximize the time in the cooler.

Additonally, as I am only drawing this up in my head and have ZERO experience with an oil cooler on a Air Cooled VTWIN. The Oil cooler will be mounted higher than the oil filter, will this cause additional strain on the pump? Potentially causing an earlier failure?

Just as an FYI - I was reading through the 107 manual on XMAS :D It had said unless your oil is continually running >280F. (Ideal temp is 250-280)There was no need to run an oil cooler. On the flipside if you were seeing temperatures below 180 constantly to add a cover to your oil filter. Just food for thought!

I just grabbed one of the oil temp gauges on your oil cap. Living in Dallas I am keen to see temps come summer time. I rode the other day in 50'ish degree weather and was seeing temps around 180-200 running through traffic. Long runs I was getting down to 150-160.
There is no wall, I have a tube on the inlet side to discharge the hot oil at the top of the cylinder and flow down and back out. The oil would be in contact with the outer wall and allow heat to disipate through the walls/fins on the outside.
 

Fibersnake

Banjo Playing PsychoBilly
BWG56,

That should work though I do not see a great deal of efficiency in it, but nonetheless it should provide some heat disapation as well as extra oil capacity. Is that tube going to be in postive contaact with the side walls. I it appears that the tube is being supported by the end cap and thus not allowing the end cap to be spun off if the tube is solid to side walls, if not and suspened, even less efficinet but still should provide some thermal transfer and cooling. Also just an idea, but if something like that was to be made, assuming it was CNC out of solid cylinder, than the far end cap could be made intergral to cyclinder since no need to remove. If being made out thick wall tube/pipe different scenario.

Here's an idea to consider. You could go with larger tubing and have it precissioned fromed around a jig to exacat deminsion (so that the coils will be in constant contact with interior wall of cylinder-sort of an interference fit) and have it be one long coil with return up center of coil and swag to outlet. That way you would have lots of coil contact to the sides of cylinder for increase transfer and basically have a dry cylinder. Things to consider though is tube would have to be fairly larger to insure no undue restrictions that could result in improper flows. Just ideas
 

Magoo

Dog Locked
I have an x-ray of a BD oil cooler, all it is, is a tube going up one side to the top and down the other. No coil, nothing fancy.
 

BWG56

Guru
Fiber, no the inlet tube is not connected or touching the bore, and would spin off with the end cap, it is there only to pump the hot oil out at the opposite end of the cooling tube, the hot oil would be in contact with the inner diameter of the tube thus disipating some heat. Yes the bore could be a blind hole to eliminate the one end cap.
This is just my idea of what I think it would look like, I don't have any intention of making one but thought I would share my ideas with you guys that are interested in making one.
 

Fibersnake

Banjo Playing PsychoBilly
Fiber, no the inlet tube is not connected or touching the bore, and would spin off with the end cap, it is there only to pump the hot oil out at the opposite end of the cooling tube, the hot oil would be in contact with the inner diameter of the tube thus disipating some heat. Yes the bore could be a blind hole to eliminate the one end cap.
This is just my idea of what I think it would look like, I don't have any intention of making one but thought I would share my ideas with you guys that are interested in making one.
BWG56,

Just throwing some idea around, but got thinking, (I need to stop that only gets me in trouble), but on the coil idea, without running numbers, it may be hard to do when you consider the bend radius of the tube (depends on material) and the relatively small inside bore. Also looking back it appears that you may were looking at a stash tube to use. which would be much easier and require less fabircation. So with that in mind, your idea would be the simplist and easy to make, not sure of how efficient but should provide some cooling for sure.

Thanks for helpin me get the old brain in gear and putting it to work. Hell if I get motivated enough, may even dust off the FEA skills and see if could figure up numbers. Then again most likely will just enjoy my time with the family, breathing USA air and if the weather is not artic base go riding.

Good luck
 
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Fibersnake

Banjo Playing PsychoBilly
OK, so heres what I got at the moment, no finite analysis or anything. One showing the divider method and the other showing the tube design.
A bit of work for something that may not be needed.
Nice CAD work Ringo! Hell even got the o-ring listed :2thumbs:

Funny for as I think for some of this is just an excercise in putting some of ours skills to work (that is some cases such may have been awhile i. .e me for example) for as you indicated, for something most of do not need (know I have been fine for 7 years without one).

Another idea to throw out there, plate and tube, Have some stacked plates made for fin with accurate holes, throw a small outside diameter plate between fin plates, run a large tube from one in up the plates, maybe 90 pass and back down the other side and on out. Only extra capacity would what the tube itself had, but would get more direct transfer for colling, would even be better if one could get a 4 pass into such and insure no excessive restriction in tube total tube length and diameter.

Once again nice CAD Drawing
 

BWG56

Guru
ringo,
I would say that it seems we're sniffen up the same tree, we're pretty much the same in concept with your 2nd drawing:2thumbs:
 

ringo

Active Member
I have no idea of the internal make up, but with the very limited space in these coolers I highly doubt theres anything of novel design happening. They all work off the same principle (forced convection heat transfer ) I wouldnt suggest the 8 in model for a big twin.
 

Five Five

Well-Known Member
It woud be interesting to know what the temperature is going into the oil cooler and what the temperature is coming out... I cant imagine it would have very much retention time in the cooler to provide any significant drop in temperature..anybody have any data ?
 

Kiwirider

Active Member
I know this is an old thread, but here's my 3c. As the tube sits vertically. Have the inlet line finish at the cooler base (no internal tube) so the inlet is filling the cooler at the base of the cooler. Then have an internal tube from exit port to just below the top of the cooler (maybe 1/2" clearance). That way when you fill and drain the oil at service, the cooler will self purge the air from the cooler cylinder. If the tube was on the inlet side, it would hold a considerable sized air pocket. Something to think about.
 

Kiwirider

Active Member
I had a quick look inside the oil line ports on my cooler before I connected it today. It looked like there was a tubed side and a baffled side. They were both definitly different though.
I connected the inlet line to the tubed side.
 
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