Okochi Ironworks Co., Ltd., Yoshinobu Town, Hamamatsu City, 1953-55
大河内鉄工所
The ad is a bit confusing as I don't understand why "BIC Motor" is in the corner of it. After a lot of sleuthing I managed to find what I'd consider to be an authoritative reference in the Hamamatsu City Central Library at this link where some detail on the early motorcycle history for the area is given. According to the Hamamatsu City Cultural Heritage Digital Archive, Okochi Ironworks made a 90cc 4 stroke machine in 1953 called the 'Silver Bell' (シルバーベル号), and then by 1955 was making a 125cc motorcycle with the same name.
