Does the 185 Zero runs hotter than the 185 CDI due to the lack of Nitro in fuel?
My experience says yes, more attention needed to ensure high speed air past the engine.
And therefore the engine is not the best option for high temperature environments?
No, not due to temperature up to 30C, no experience running it at higher ambient temperatures. The reason I ran into problems was due to the fuel temperature. With an oil content of 10% the vapor pressure of the fuel is low. I got problems in maneuvers like the stall turn, vapor lock in the fuel pump. My workaround was to cool down the fuel (to 5C), see previously posted graph. Have not tried to pressurize the fuel tank.
From reading the all the above, I understand that vibration is increased compared to regular 185 or CDI and the YS damper should be used even with the Hyde soft mount?
I have no measured data confirming your statement, however, the mass/spring system comprising the steel piston in the fuel pump and the valve spring, is affect by the dynamic behavior of the engine itself. The less vibration the engine has at idle, a steady idle can be obtained at decreasingly lower rpm. Hence the need for a viscous damper. I have tested successfully two mounts:
1. YS mount.
2. CK Aero: YS Hyde Soft Mount
Both of these mounts have the same interface, and uses the same viscous damper.
Arnstein