So you are ready to pass on your old 120volt 1000amp controller now and advance in to the unknown.
On investigation of further cooling concepts (mainly total immersion).
Laquering over the magnets and rotors will protect the magnets from corrosion and improve the structural integrity of the rotor.
Composite sleaved tube housing design and CNC stator mount/ end plates with a mirror image will cut down cost and manufacturing time along with the constant diameter shaft and common seals and bearings for both ends and between stators on longer designs say 4rotors.
This design concept allows for further expansion on the multi rotor/ stator concept with the enhanced cooling you were looking for.
Suggested volume for radiator cooling is 1.5 times rhe immersive volume of the motors internal free air space.
the 600's came back on Tuesday and had one in the bike the same afternoon.
It performs ok and doesnt cut out but has rough regen especially at low speed.
Anyway I made a new dash board and installed a blue led in between the 2 kelly led's which lights up when the cooling system is running so now i dont forget to turn it on.