It is my understanding that when the castor oil gets hot, it will form a protective coating on the engine components, that if by chance the engine is running too lean, will protect those parts. I guess over time that coating becomes unsightly and difficult to remove, but I like knowing that things in my engine are lubricated no matter what. All the manuals I've read (Magnum, Super Tigre, O.S. all talk about using castor oil in your fuel. Magnum says you must use it for break in, OS and I believe Super Tigre suggest fuel with castor oil. I love my OS46AX. It has withstood me running it too lean on my first time starting an engine, has been through two serious crashes, and runs the best out of any engine at our field. When I took apart the engine this last time, under all the dirt was a nice coating of oil. The dirt cleaned off easily, I used castor to lube all the parts to put it back together, and I use Wildcat Extra fuel with 18% lubrication, 20% of that which is castor. I've also added castor to other fuels to always have 20% of my lubrication be by castor oil. I think it's helped me, but I guess its just my opinion.