So maybe I'll keep using my current 60:40 blend. Plane gets more slimy, but I like what's good for the engine. Thanks for all the inputs.
ORIGINAL: blw
100% castor and no nitro is FAI fuel.
Castor oil will provide benefits to any glow engine. It should be flushed out if the engine is going to sit for a length of time. Otherwise, no problems using it.
By "flushed out" I suppose you mean an alcohol bath? I'm wondering if something less tedious like just running a tank or two of 100% synthetic fuel through it in the fall (at slightly richer setting) would be good enough???