RE: YS 110 Fuel and Such
Yes the Pro Pattern 25% is fine and will work well in the engine.
Castor is OK but not recommended for the oil to lube the cam gear prior tot he first run....BUT don't drip it down the pushrod tubes. Removed the cam gear cover and put it directly on the cam gear. There are little lifters or cam followers might be the more correct term. These will prevent the oil from from getting down to the cam. So put it directly on the cam itself.
I DON"T use any Castor in the engines. Castor won't hurt the silicone seals and such. However the high temps of the 4 strokes along with the way Castor gums up and carbons up the engine is bad for it. Today's fuel with Synthetic oils are way better at lubricating the engine than Castor is and they run clean.
Omega fuel has castor in it. You should run Cool Power instead. They are the same fuels except Omega has Castor and Cool Power is all synthetic.
NO you don't need to run extra castor in it. This seems to be a practice followed by many folks. You will have poor performance. 15% is the minimum nitro content recommended for YS engines. If you take some 15% nitro and add oil to it you will dilute the fuel down so it is less than 15% Nitro. 4 strokes like higher nitro fuels. It allows for broader needle adjustments and better cooling. While the engine will run on a Cool Power 15% sport fuel it is recommended you run a YS 20-20 blend the Pro Pattern blend is a 20% oil blend and 20 or 25% nitro Pro Pattern would definitely be better.
I understand your concern about different fuels. You can run the Pro-Pattern blend in most if not all other engines too.
I run Cool Power 30% Performance heli blend in all my glow engines from small 25's up to larger Moki 2.1 engines. The 20 or 25% pro pattern Cool Power is an excellent fuel and is designed to run it YS engines it is also a little cheaper than the 30% heli blend.
Troy Newman
Team YS Performance