Oil cooler, what to use as a core.

No if you look closely, you'll see the top mount is fitted to the tube in the steering head brace. The bottom mounts fit to the two holes at the bottom. It's just ugly as sin. :sick:
Steve

Yeah it's dirty. It needs clean and paint but it is stock Kawasaki LTD cooler.

1.2" ID, correct for the bigger fours.
Steve

Just a little follow up.
Finally got around to getting a cooler mounted up.
Picked up a core from semi-local bike junkyard, I'm not even sure what it came off of. I was able to use the banjo fittings that came with the cooler and bent the hardlines to point up and over the head. Flared the lines and clamped the 3/8" id hose directly to it.
Looks fairly clean and gets the lines out of sight, oil light goes out immediately with the lines running over the head because the cooler holds oil when the bike is shut off rather than draining back into the case.
I suppose that will also help when checking oil using the sight glass also.

At any rate I'm glad it's done!

nevermind... already addressed the issue. :blush:
(I originally mentioned concern over possibly using a low-flow cooler from a plain-bearing bike on a motor requiring high-flow. It looked like the issue was covered previously, so I deleted the comment that Steve replied to.)

Looks good with the lines hidden!

I didn't want to say anything but now that you brought it up, yes, they require 1/2" !3mm ID fittings and cooler. 3/8" will work but being the "Big end" gets the oil first, the top end may be getting less oil than it needs. That's why I drilled out the fittings on the cooler and made my own fittings for it. It was a ZX7 cooler and the hard tubes were much less than 3/8"'s. :dry:
Steve
kzrider.com/forum/2-engine/600430-zx7-z1-oil-cooler

I actually did figure out it's from a gs750, which I understand to be very similar to our engines, as in low pressure, high volume.

I based my decision on the passageways from the stock oil pressure block bolted to the back of the motor.

I think my setup will work fine with what I have, larger lines might be more effective at cooling, slowing down the flow so the oil stays in the cooler longer.

Regardless of line size the oil has to flow through the same size hole to get back in the block.

The hard lines that came with my oil cooler are larger that what I had on my little 550 gpz's and the 3/8" id hose fits tightly over it.

I'm comfortable with my decision, but I do still appreciate the scrutiny, just to be sure.
All opinions welcome! Thanks.

For max cooling, you want the highest possible temp differential between the air and the oil. That happens when the oil flow volume is greatest. It may not drop the temperature as much, but because a higher volume of oil is losing that little bit of temperature, the overall heat removed is greater. Think of it in terms of what will cause the greatest temp difference between the air and the radiator (assuming the radiator stays the same size). Keeping the radiator hotter by flowing more oil, will cause the radiator to transfer the more heat to the air.

The oil galleys are 13mm 1/2". Going to 3/8" will slow the flow of oil. It's not so much the cooling I was concerned with, it was the oil starvation by restricting the flow.
Steve

You gotta look at the entire system, not just the line ID. Typically the fittings that attach to the engine are the restriction point. 3/8" ID is typically as large as you can manage since there is a restriction somewhere other than the lines.

I managed to get 3/8 NPT with 1/2" ID barbs.
Steve