RE: 140 rx fuel
I have over 300 flights on my #1 140RX. It is fine with most any good fuel. I have run both Cool Power 10% and 15% with good results. I would definitely change the bearing even before you run it the first time. The stock one will not last too long and you will find yourself removing the engine from the plane to change it rather quickly. I use the sealed bearing from the EFI version ($25 from tower -stock code- LXWY09 ) and have 200+ flights on it, and it is still fine. You will love this motor.