I agree with almost everything above. Mike's right about castor but I just hate running it anymore. I found that running some 80/20 (80% methanol and 20% castor) at the end of the flying session can provide terrific corrosion protection. I would keep a separate tank full that the engine would draw from externally - run for just 20-30 seconds, then run the engine dry. I don't bother anymore because my ariplanes spend their non-flying time in my dehumidified basement workshop.
As an aside, the other MAJOR cause of bearing failure (for me) was nickel peeling off the cylinder wall of the OS liner (especially the first OS .61RF ABC-P engines back in the mid '80s). Solved that problem with Performance Specialties (Dave Shadel) piston and liner sets.
The 2 biggest causes of bearing failure (under normal conditions) are water/moisture (causing rust) and dirt...so avoid flying in mud at all costs .
Good Luck, you'll love the OS 1.40!!
Will B.