Gents, a short note about overheating, technical matters,

As we can read in the thread about the engine for a KF, one of the results of overheating of the old ringed engines can be, losing of tension of the piston ring,
http://www.rcuniverse.com/forum/fb.asp?m=10028465

the problem for the ABC engine, in my opinion, is reduced quality of oil, loosing of ability to maintain a oil film between piston an liner to prevent metal to metal contact. I do not use castor oil, only synthetic oil in the fuel!
I also did detect destroyed ball bearings as result of axial displacement of these bearings in the crankcase after a moment of overheating. See picture, black oil on the fuselage.

For this reason I prefer my detection on all my engines also in the Simla next year whatever engine I will use, MVVS (ABC), ST G60 (ringed).

Cees