For what it's worth, here is one more tidbit.

I just bought a new ringed Enya 50SS 2-stroke. The instructions that came with it say simply to run it rich for the first hour and after that lean it out to a normal (slightly rich) setting. The instructions say the engine may take 2~3 hours to reach its peak performance.

Interestingly, the instructions that come with the ringed OS 50SX say to run it 4-storking at full throttle for the first minute then lean it to 2-stroke for 10 seconds then back 4-stroke and repeat until the first tank is empy. OS doesn't distinguish between ringed and non-ringed breakin. The instructions for the FX engines are the same.