I think a better and newer oil cooling system is the way to go on Utility ATVs. I notice my friends 2006 500 Foreman has two oil coolers. All ATVs have oil pumps anyways so why not just have engines hold more oil and circulate the oil longer distances through a larger fan assist oil cooler to cool the oil down which intern cools the motor.

On a oil cooled system there is no vital thermostat or water pump to fail, if the fan on the oil cooler fails its no big deal because its just there to assist, its not a vital part like the fan on a radiator. If a oil cooler get clogged with mud the engine is still fine just circulating the oil because the cooler is just a cooling asist part also. If a radiator gets clogged its over heat time and it must be cleaned out.

They should just make oil coolers the size of liquid cooled radiators are now with large fans and instead of carrying around coolant just have the ATVs carry extra oil to circulate through these larger oil coolers.

Advantage,, You have no coolant to flush or worry about anti freeze ratios and freezing up. Your regular oil change would also be maintaining you cooling system all at once.

Does this make sense?

 

i dont beleave it would run cool enough to make it work. the oil coolers ive seen aslo rely on air cooling to help. where they go slow and thru mud to clog up the engine i think it would still run to hot and also loose power. thats just i think but probably wrong lol.

 

I have always been a very big fan of air/oil cooling on very low stress and low power engines like all Honda utility quads (except Rincon and now the new 420 Rancher) and the low power XR400/250, 300EX and 400EX. However when power goes up they often need more cooling. When Honda come out with water cooled XR650R they got rid of the radial head design. The radial head arrangement could handle higher temperatures. So with the water cooling Honda no longer needed the costly radial valve arrangement. The water cooled XR650R could also hang together after high horsepower mods while the old radial valve XR600R was a time bomb. Honda was tired of getting beat by the KX500 2 strokes and the result was the rock solid XR650R.
I do not understand the need for water cooling on the 420 Rancher. I suppose that marketing factors come into the picture because Honda can now hype the all new tech liquid cooled 420. When my dirt bike rides lean toward the long and gnarly rather than long and fast I will always roll out my XR400 instead of the XR650R because it is lighter, makes enough power, gets better milage, and has no radiator or hoses to break in the get offs.

 

i believe the amount of oil around the top end of an engine is not enough to ensure cooling the head/jug/exhaust port like water cooling can. there is usually just a trickle of oil going to the top end (enough to lube the cam, rockers, ect...) but this is where the bulk of heat is generated.

it is the job of the oil to cool the piston, tho, and along with the friction heat, the oil could use a cooler also, but not the size of the radiator. oil is supposed to be 180*-200* to perform properly. a huge cooler could supply oil too cold to perform as designed.

monty

 

I have an atv that is oil/fan cooled. And it has only gotten too hot 1 time. But i would prefer water cooled 4 sure