I’ve been running Castrol 20-50 in my 20B to this point (about 25 hours).  Now that it is about ‘broken in’, I’m considering changing to synthetic.  Everyone has their favorite oil, but I’m thinking the Idemitsu racing oil; “specifically engineered to meet the unique requirements of a rotary engine”. http://www.idemitsu-usa.com/page_211.htm, would make sense.

It comes in 10-30 and 20-50.  Considering typical operation at high power, about 5000 rpm, and at temps of 180 -210; I’m thinking stay with 20-50.

Comments?

Al