If you havent noticed, I started doing this mod....
I am going to have to shave down some of the "engine names" for formatting reasons.... here is the new list.... if anyone wants to add engines to it, LET ME KNOW AND I CAN GET THEM UP AS OPTIONS.
for now... go in your profile to select engine type and MAKE SURE YOU CLICK "ALWAYS SHOW ENGINETYPE"
No Engine Yet
GEBE R/S 35cc
GEBE R/S 25cc
GEBE Tanaka 40cc
FBE R/S 35cc Friction
FBE Tanaka 40cc Friction
Actually...there's no such engine as Russian M21. What you are talking here about, is the "D" series of engines - D4, D5, D5M, D6, D8 and D8E (lined up by the production year). Basically same layout, but some details are different.
The chinese engines were copied from D4 at 1950-s hence the similarities.