Oil cooler

[AzBob_imp]

I think its a poor design. They should have at least let you drain the cooler with a primer to refill. Leaving a full quart (20%) of dirty oil in the system just does not make sense. Remember this oil runs through the tranny collecting a lot of metal and brakes down much quicker. They would have been much better served to make a water cooled radiator the same size if there going to put it there at all, this would have allowed fresh oil changes.

I'm not 100%, but I'm relatively sure that an oil's ability to keep contaminants in suspension is unrelated to its sheer strength. Also, once you're past about 500 miles, your transmission really shouldn't be shedding any more metal than your engine, which is to say, nearly none.

Quote:They would have been much better served to make a water cooled radiator the same size if there going to put it there at all
And then they'd have had to put the overflow tank somewhere and run the giant coolant lines all over the place. A water-cooled radiator the size of the oil cooler we have now wouldn't be very performant. Much less so than the oil cooler. The oil picks up the heat of combustion by washing over the metal directly; the radiator fluid merely runs near the hot areas through the water jackets -- it's much less efficient at removing heat than directly cooling the oil.

"Then why are all modern automobiles liquid cooled?" Because you can only run so much oil in the engine before the crankshaft turns it into a frothy mess. You can increase the cooling capability of a liquid cooled automobile simply by increasing the capacity of the radiator. You can't increase the efficiency of an oil cooler by increasing its size because that would necessitate an increase in oil volume, which has an upper limit dictated by the needs of the engine.

The "13 service manual has an oil flow diagram on page 4-2. It looks as though there is a 2 chambered oil pump where one chamber pumps through the oil filter and into the lower engine (cylinders and below). The other chamber pumps oil into the cooler and from the cooler, into cylinder head channels around the spark plugs. From the cylinder head it flows through a channel with the EOT (engine oil temperature) sensor and then back into the sump. This design is consistent with the Honda engineers worry about high temperatures surrounding the spark plugs.

There is a high temp "idiot" light that comes on when the oil temp is too high. I wonder if our friends in Arizona or OZ have ever seen this come on when riding in stop and go traffic on very hot summer days?

You could try removing the cooler (I'm not recommending this) and then monitor the high temp light to come on under a variety of riding conditions like Pterodactyl suggested. A temp gauge would be more useful. Does anyone know of a gauge that can be wired into the EOT sensor?

Personally I don't have a problem with the looks of the cooler but as others have mentioned there are alternatives out there.

Earl's has a nice line of coolers that are designed to fit between the forks (2 different widths, curved vs straight, and variations in the number of "rows"). Mounting the coolers between the forks would involve moving the horns and also there would be a potential problem with the brake lines being just behind the cooler.

Japan webike sells [url=http://japan.webike.net/products/21220082.html]Earls oil cooling kits designed for the CB750, CB900 and CB1000F. They are pricey though and you may be better off ordering the parts directly from Earls [url=http://www.earls.co.uk/earls100/earls_shop/index.php?main_page=index&cPath=14_38&zenid=32051fs1tutjtkm9711rapdke0](link).

Earls "curved coolers"



Another protector for the stock cooler that may be more visually pleasing.

I've ridden my CB in extended 120*F heat in stop & go traffic where I was CERTAIN the overheat lamp would light, but it hasn't, so far.