Motoki started his entertainment career as a member of boy band Shibugakitai (シブがき隊) (name of the group is abbreviation of tough (渋い, Shibui) kids (ガキ, gaki), which makes it an homonym of astringent persimmon (渋柿, Shibugaki)) that made a debut in 1982 under the management of Johnny & Associates. They were top idols for a good part of the eighties in Japan.