Prop: Yuriy's own wooden 13,4x5,9 works the best.
Plug: Russian KC-2 is the best but difficult to get. Also Enya 3 or 4 work.
Fuel: 80/20 full castor fuel works well, but you can use 1/3 of oil synthetic to keep things cleaner. Not all synthetics work, though, so it's always nice to compare with full castor fuel if problems occur.
Another option is 85/15 fuel with Maxima 927 oil.
Make sure that squish clearance is set to 0,6mm.
L

As the manufacturer Yuriy Yatsenko advised me a few years ago, the engine is designed for 20% oil, for long work it can be pure castor oil, for eternal work in half with the Motul micro 2t popular in our region, candles in my experience: OS F, A3, LC3, the screw worked well Rev-Up 13x7

Remember that it's not the most powerful engine, model weight shouldn't be much over 1600g/56oz. L