My Inspire-90 with Saito-125 is completed but first flight will probably not be until next weekend
as there has been engine mounting issues and weather delays.
I first mounted the engine inverted and did some engine run-in tests on the ground.
I have now remounted the engine sideways.
In this model the tank is far above the carb when the engine is inverted and I strongly recommend
against an inverted engine setup. Fuel will run down into the carb.

I used a Saito metal mount for the engine. A soft mount may be better but I am not sure
how much better it will minimize airframe vibration.
Although I have carefully balanced the prop the vibration is quite large at full throttle.
This is typical for a model with light-weight plug-in wings.
The canopy and wings are held in place with M4 metal screws into metal T-nuts.
Metal in metal won't stay put under vibration and it was impossible to keep the canopy
screws in place; they would just vibrate out. I have now replaced them with
M4 size nylon screws that stay put. The two metal screws that hold the wings on
did not vibrate out but it is probably still a good idea to also replace those with nylon screws.

With a 5-cell A-size battery pack located between the receiver and tank the CG
came out about right in the forward part of the recommended range.

I have made some other minor changes and will let you know later how it flies.