I take it your still runnuning the Kawasaki gpz 900r engine
As you know that family of engines went 900r, 1000rx, zzr1100, and zzr1200.
all similar bottom ends.
Have done some massive modifications to ths 1000rx and the zzr100.
The oil migrating to the cylinder head and staying there was there biggest issue as the only drain back was down past the timing chain cavity and through the insufficient drain holes behind the ignition .I have put the oil feed both above and below the level , as the engine has 2 sumps and twin pumps I found the most effective place to run the drain line was to were the balance shaft was, that feeds directly to the main sump which has the engine feed oil pump( the more critical one to be kept fed )
In the top of your cylinder head is 5 screw out core plugs , and they are in there tight..
removing these items will give you access to the water jackets. fill this area with engine oil and do not put the plugs back in (this will let the oil expand with heat) so now your engine will take approximatley 6 litres of oil instead of 4 .(this oil will not drain down to the sump when the engine is stopped , it is captive in the jackets..
NEXT :remove the water pump and radiator then throw them in the bin, plug the water pump hole, remove the water housings from the rear of the cylinder head and the front of the block and replace with 20mm frost plugs..
Number 2 of the twin pumps feeds the oil cooler , with methanol your cooling will be sufficient.
Kawasaki's fix to the drain proplem in the later models was the fitting of the 2 reed valves in the rocker cover , this stopped the vacum issue in the cylinder head ,thus helping the oil to return to the sump ...
this worked well enough on a street engine but not well enough for a race engine.
In saying this .. if you have not got a breather in the rocker cover ...you need one....
I employed this system to a covered in speedway bike for 5 race seasons ... and had absolutley no issues with overheating.
Hope this is of some help ..
IT IS ALL A RACE AGAINST TIME.
TIME WAITS FOR NO ONE.
HOW FAST CAN YOU GO ?