I am installing an RCG 20cc gas engine into a new model, and I need to know what the prop shaft dia. and thread size is. I need to know, so I can order a spinner adapter for my new model.

The instructions state to use 25~40/1 oil mixture. From what I read...it looks like I'll be using 25 to 1 ratio for my oil/gas mixture. I've been told to use outboard moter two cycle oil...any suggestions ?

I would like to replace the carb on this engine...any suggestions ?

What replacement spark plug should I use ?

This is my first gas model, all my other models have been glow fueled. I built a 60~90 size Big Stick and mounted a RCG 20cc engine to the nose.

Thanks for the help,
Soft Landings Always,
Bobby of Maui