Precision Oil-Cooled Cylinder Heads : V-Twin Forum: Harley Davidson Forums

Unyalli · 07-29-2009, 03:20 PM

Curious searching this forum on this turns up nothing. Harley has developed an oil-head sporty in the xr1200 and there's no buzz? Nobody want's to retro-fit this?

claydbal · 07-29-2009, 04:20 PM

please explain oil head. HD motors have had oil run across the heads and absorb heat since before baseball. all air cooled motors are also oil cooled in some fashion. what makes the new sporty head different?

Unyalli · 07-29-2009, 04:47 PM

Search on Precision Oil-Cooled Cylinder Heads or Oil-Cooled Cylinder Heads XR1200 in Google and you find all kinds of articles touting the new XR1200. They all mention oil-cooled heads but I can't find out anything on this.

Motorcycle USA Article

ultraplusrotax · 07-30-2009, 03:49 PM

A certain amount of oil at a certain pressure is needed for the lubrication of 4-stroke or Diesel-engines.
If we rise the volume of the oilpump then it will cool the engine by picking up the heat at stressed parts and getting rid off the heat via a radiator or an overly large oiltank, just like the swingarm of Buell, or the enlarged crankcase of Ducati -singles 160, 250, 350 and 450 cc, or the side-mounted oiltank on Buell or XR 1200 .
My oil-cooled bike runs fine.

Unyalli · 07-30-2009, 05:29 PM

I guess it has been discussed over on another forum.

http://xlforum.net/vbportal/forums/s....php?p=1721601

claydbal · 07-30-2009, 05:42 PM

thanks, so its taking the oil drains and using them as a portal to an oil cooler?

Phaedrus- · 09-06-2009, 10:42 AM

Quote:

Originally Posted by claydbal

thanks, so its taking the oil drains and using them as a portal to an oil cooler?

An old thread I know, but if was not answered, the XR1200 heads have extra oil passages milled in them. There is an additional oil feed that fills the heads with oil, draws off heat and drains it separately out to the oil tank. This oil flow is completely separate from the top end oil flow through the rocker arms, and it is an effective means of pulling down the heat in the heads. The heads also require a different head gasket because of how the oil passages are formed. Maybe if HD did this on the CVO 110s, they wouldn't be having such a problem with the heads and cylinder liners...