Used YS 60 FS

Arrived YS 60 FSH motor disappointed me a bit, that was made successfully bid in Yahoo Auction at 2,980 yen without competitors.
There exists no worn away evidence outside probably with very short period of time operation, but the ringed piston has apperent shinny spot at exhaust angular position also at opposite side meaning that the motor had been operated in very critical condition, too lean mixture loosing main needle valve setting. As a common sense, Ringed Piston has enough tolerance between the cylinder wall compared with ABC or AAC, in spite of the advantaged circumstance, the piston has shinny spots around the ring at higher position?
Probably, a former user must be failed in the initial break-in stage and a miserable YS 60 FS motor has been thrown away because of poor performance.
Crank shaft supporting main bearing has uneven ball wear not because of ordinary use but because of operating in the critical condition.
Now, I made up my mind to save this motor and to survive acquiring the original performance as designed by Mr. Yamada.
Removing concave surfaces on the piston wall caused by over-heating handling would be carefully reshaped avoiding unnecessary slipping resistor, piled carbon and sludge would be removed and the main bearing # 6903 would be replaced.
Following the Physical principle these kind of task is not always difficult.
Hoping this weeping and beaten-up motor would fly into the blue sky like a Phoenix in very near future.