ORIGINAL: Jim Thomerson
There are engines and there are engines. Iron piston, ring, ABC, revlite, etc. Each requires its own fairly specific breakin routine. The question as asked is too general.
Jim
More specifically, how would you break in an OS .50 SX Ringed engine with the stock muffler...
http://www2.towerhobbies.com/cgi-bin...&I=LXALM2&P=ML