Interesting.... I use Omega (castor/syn blend) my other engines and in the older YS120 _ (it's about 18 yrs old... the first 120 offered by YS and still running strong.). but the literature says it's ok to do so... but limited to 2% castor on the 170. I am using VP 20/20 for breakin then planning to use 30% pattern or Cool Power 30% Heli for flights.
ORIGINAL: rcflyer4fun
I had a new ys 170 and I had trouble breaking it in. I gave it to Mickey L. and he broke it in for me. He said you need to use fuel with castor oil in it for break in.